BlackTreeCVE Intelligence
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Full vulnerability report · 2020
CVE-2020-8450High confidence

Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy

Unknown · Unknown

7.3HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:Critical, raised one band.upgradedsince 23 Oct 2026

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 71.79% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Unknown Unknown and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 3 daysRemediation target: Within 90 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Distribution package intelligence

Release-specific package status

Alpine, Debian findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

7 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Alpine v3.23v3.23 · mainsquidVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.4.10-r0Alpine Security Database ↗Source updated 23 Oct 2026
Alpine v3.22v3.22 · mainsquidVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.4.10-r0Alpine Security Database ↗Source updated 23 Oct 2026
Alpine v3.21v3.21 · mainsquidVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.4.10-r0Alpine Security Database ↗Source updated 23 Oct 2026
Debian trixietrixie · sourcesquidVendor fix publishedDebian records a fixed source-package version for this release.4.10-1Debian Security Tracker ↗Source updated 24 Oct 2026
Debian bookwormbookworm · sourcesquidVendor fix publishedDebian records a fixed source-package version for this release.4.10-1Debian Security Tracker ↗Source updated 24 Oct 2026
Debian forkyforky · sourcesquidVendor fix publishedDebian records a fixed source-package version for this release.4.10-1Debian Security Tracker ↗Source updated 24 Oct 2026
Debian sidsid · sourcesquidVendor fix publishedDebian records a fixed source-package version for this release.4.10-1Debian Security Tracker ↗Source updated 24 Oct 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2020-8450 · CSAF 2.0 · revision 19 · interimSUSE Product Security TeamCVE-2020-8450
1 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • squid as component of SUSE Linux Enterprise Server 11 SP1 for Teradata
Summary
An issue was discovered in Squid before 4.10. Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy.
Remediation
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2020-29316

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

An issue was discovered in Squid before 4.10. Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy.

What

An issue was discovered in Squid before 4.10. Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy.

Why

The product does not correctly calculate the size to be used when allocating a buffer, which could lead to a buffer overflow.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

An issue was discovered in Squid before 4.10. Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy.

Why

The product does not correctly calculate the size to be used when allocating a buffer, which could lead to a buffer overflow.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Incorrect Calculation of Buffer Size → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-131 ↗

CWE-131: Incorrect Calculation of Buffer Size. The product does not correctly calculate the size to be used when allocating a buffer, which could lead to a buffer overflow.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CLowConfidentiality impact: A successful attack can cause a limited loss.ILowIntegrity impact: A successful attack can cause a limited loss.ALowAvailability impact: A successful attack can cause a limited loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-131
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-2023-1361Squid: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Squid ausnutzen, um Informationen offenzulegen, einen Denial of Service zu verursachen, Sicherheitsvorkehrungen zu umgehen oder Code zur Ausführung zu bringen.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-700Multiples vulnérabilités dans les produits IBM

g/CVERecord?id=CVE-2020-15049 Référence CVE CVE-2020-15810 https://www.cve.org/CVERecord?id=CVE-2020-15810 Référence CVE CVE-2020-15811 https://www.cve.org/CVERecord?id=CVE-2020-15811 Référence CVE CVE-2020-24606 https://www.cve.org/CVERecord?id=CVE-2020-24606 Référence CVE CVE-2020-5258 https://www.cve.org/CVERecord?id=CVE-2020-5258 Référence CVE CVE-2020-5259 https://www.cve.org/CVERecord?id=CVE-2020-5259 Référence CVE CVE-2020-7595 https://www.cve.org/CVERecord?id=CVE-2020-7595 Référence CVE CVE-2020-8177 https://www.cve.org/CVERecord?id=CVE-2020-8177 Référence CVE CVE-2020-8449 https://www.cve.org/CVERecord?id=CVE-2020-8449 Référence CVE CVE-2020-8450 https://www.cve.org/CVERecord?id=CVE-2020-8450 Référence CVE CVE-2021-20385 https://www.cve.org/CVERecord?id=CVE-2021-20385 Référence CVE CVE-2021-20386 https://www.cve.org/CVERecord?id=CVE-2021-20386 Référence CVE CVE-2021-20389 https://www.cve.org/CVERecord?id=CVE-2021-20389 Référence CVE CVE-2021-20419 https://www.cve.org/CVERecord?id=CVE-2021-20419 Référence CVE CVE-2021-20426 https://www.cve.org/CVERecord?id=CVE-2021-20426 Référence CVE CVE-2021-20428 https://www.cve.org/CVERecord?id=CVE-2021-20428 Référence CVE CVE-2021-21284 https://www.cve.org/CVERecord?id=CVE-2021-21284 Référence CVE CVE-2021-21285 https://www.cve.org/CVERecord?id=C

Official advisory ↗
CERT-FR · French · CERTFR-2020-AVI-070Multiples vulnérabilités dans Squid

De multiples vulnérabilités ont été découvertes dans Squid. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et un contournement de la politique de sécurité.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2020-001627Squid におけるバッファエラーの脆弱性

Squid には、バッファエラーの脆弱性が存在します。

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
squid as component of SUSE Linux Enterprise Server 11 SP1 for Teradata
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 4 Feb 2020 · Last source change 4 Aug 2024, 09:56 UTC · CWE-131 · Incorrect Calculation of Buffer Size

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2020-29316
Product sourceVendor CSAF · SUSE Product Security Team
Remediation sourceVendor CSAF · SUSE Product Security Team
CWE sourceNIST NVD
NVD statusNVD modified after enrichment

Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2020-29316↗Vendor CSAF · SUSE Product Security Team↗CVE authority or vendor reference↗Patch or update reference↗Patch or update reference↗Patch or update reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2020-8450 · cve.blacktree.nl