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Full vulnerability report · 2020
CVE-2019-18634High confidence

In Sudo before 1.8.26, if pwfeedback is enabled in /etc/sudoers, users can trigger a stack-based buffer overflow in the privileged sudo process

n/a · n/a

7.8HighCVSS 3.1
Recommended action
Within 7 days

High technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Fix not verified
Optional official sources

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

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

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-2019-8357

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 with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Fix not verified
01

What, why and how

In Sudo before 1.8.26, if pwfeedback is enabled in /etc/sudoers, users can trigger a stack-based buffer overflow in the privileged sudo process. (pwfeedback is a default setting in Linux Mint and elementary OS; however, it is NOT the default for upstream and many other packages, and would exist only if enabled by an administrator.) The attacker needs to deliver a long string to the stdin of getln() in tgetpass.c.

What

In Sudo before 1.8.26, if pwfeedback is enabled in /etc/sudoers, users can trigger a stack-based buffer overflow in the privileged sudo process. (pwfeedback is a default setting in Linux Mint and elementary OS; however, it is NOT the default for upstream and many other packages, and would exist only if enabled by an administrator.) The attacker needs to deliver a long string to the stdin of getln() in tgetpass.c.

Why

A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

In Sudo before 1.8.26, if pwfeedback is enabled in /etc/sudoers, users can trigger a stack-based buffer overflow in the privileged sudo process. (pwfeedback is a default setting in Linux Mint and elementary OS; however, it is NOT the default for upstream and many other packages, and would exist only if enabled by an administrator.) The attacker needs to deliver a long string to the stdin of getln() in tgetpass.c.

Why

A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.

How

An attacker operating through local access may attempt exploitation with low privileges. 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.
Reference recorded

A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.

Likely attack path
local access → Out-of-bounds Write → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
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-787

CWE-787: Out-of-bounds Write. The product writes data past the end, or before the beginning, of the intended buffer.

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

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

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
CWE-787Public exploit reference
A

Official authority intelligence

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

CERT-FR · French · CERTFR-2023-AVI-0504Multiples vulnérabilités dans les produits IBM

de code arbitraire à distance et un déni de service à distance. Solution Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation). Documentation Bulletin de sécurité IBM 6998815 du 28 juin 2023 https://www.ibm.com/support/pages/node/6998815 Bulletin de sécurité IBM 7005519 du 26 juin 2023 https://www.ibm.com/support/pages/node/7005519 Bulletin de sécurité IBM 7008449 du 29 juin 2023 https://www.ibm.com/support/pages/node/7008449 Référence CVE CVE-2014-3577 https://www.cve.org/CVERecord?id=CVE-2014-3577 Référence CVE CVE-2019-10743 https://www.cve.org/CVERecord?id=CVE-2019-10743 Référence CVE CVE-2019-18634 https://www.cve.org/CVERecord?id=CVE-2019-18634 Référence CVE CVE-2019-19232 https://www.cve.org/CVERecord?id=CVE-2019-19232 Référence CVE CVE-2019-19234 https://www.cve.org/CVERecord?id=CVE-2019-19234 Référence CVE CVE-2020-8244 https://www.cve.org/CVERecord?id=CVE-2020-8244 Référence CVE CVE-2021-3156 https://www.cve.org/CVERecord?id=CVE-2021-3156 Référence CVE CVE-2022-1471 https://www.cve.org/CVERecord?id=CVE-2022-1471 Référence CVE CVE-2022-25857 https://www.cve.org/CVERecord?id=CVE-2022-25857 Référence CVE CVE-2022-25881 https://www.cve.org/CVERecord?id=CVE-2022-25881 Référence CVE CVE-2022-33980 https://www.cve.org/CVERecord?id=CVE-20

Official advisory
CERT-FR · French · CERTFR-2022-AVI-267Multiples vulnérabilités dans Juniper Networks Junos Space

d?id=CVE-2019-17006 Référence CVE CVE-2019-17023 https://www.cve.org/CVERecord?id=CVE-2019-17023 Référence CVE CVE-2019-17041 https://www.cve.org/CVERecord?id=CVE-2019-17041 Référence CVE CVE-2019-17042 https://www.cve.org/CVERecord?id=CVE-2019-17042 Référence CVE CVE-2019-17053 https://www.cve.org/CVERecord?id=CVE-2019-17053 Référence CVE CVE-2019-17055 https://www.cve.org/CVERecord?id=CVE-2019-17055 Référence CVE CVE-2019-17133 https://www.cve.org/CVERecord?id=CVE-2019-17133 Référence CVE CVE-2019-17666 https://www.cve.org/CVERecord?id=CVE-2019-17666 Référence CVE CVE-2019-18282 https://www.cve.org/CVERecord?id=CVE-2019-18282 Référence CVE CVE-2019-18634 https://www.cve.org/CVERecord?id=CVE-2019-18634 Référence CVE CVE-2019-18660 https://www.cve.org/CVERecord?id=CVE-2019-18660 Référence CVE CVE-2019-18808 https://www.cve.org/CVERecord?id=CVE-2019-18808 Référence CVE CVE-2019-19046 https://www.cve.org/CVERecord?id=CVE-2019-19046 Référence CVE CVE-2019-19055 https://www.cve.org/CVERecord?id=CVE-2019-19055 Référence CVE CVE-2019-19058 https://www.cve.org/CVERecord?id=CVE-2019-19058 Référence CVE CVE-2019-19059 https://www.cve.org/CVERecord?id=CVE-2019-19059 Référence CVE CVE-2019-19062 https://www.cve.org/CVERecord?id=CVE-2019-19062 Référence CVE CVE-2019-19063 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2020-AVI-063Multiples vulnérabilités dans les produits Apple

ité Apple HT210920 du 28 janvier 2020 https://support.apple.com/en-us/HT210920 Bulletin de sécurité Apple HT210921 du 28 janvier 2020 https://support.apple.com/en-us/HT210921 Bulletin de sécurité Apple HT210922 du 28 janvier 2020 https://support.apple.com/en-us/HT210922 Bulletin de sécurité Apple HT210923 du 28 janvier 2020 https://support.apple.com/en-us/HT210923 Bulletin de sécurité Apple HT210947 du 28 janvier 2020 https://support.apple.com/en-us/HT210947 Bulletin de sécurité Apple HT210948 du 28 janvier 2020 https://support.apple.com/en-us/HT210948 Référence CVE CVE-2019-11043 https://www.cve.org/CVERecord?id=CVE-2019-11043 Référence CVE CVE-2019-18634 https://www.cve.org/CVERecord?id=CVE-2019-18634 Référence CVE CVE-2020-3825 https://www.cve.org/CVERecord?id=CVE-2020-3825 Référence CVE CVE-2020-3826 https://www.cve.org/CVERecord?id=CVE-2020-3826 Référence CVE CVE-2020-3827 https://www.cve.org/CVERecord?id=CVE-2020-3827 Référence CVE CVE-2020-3828 https://www.cve.org/CVERecord?id=CVE-2020-3828 Référence CVE CVE-2020-3829 https://www.cve.org/CVERecord?id=CVE-2020-3829 Référence CVE CVE-2020-3830 https://www.cve.org/CVERecord?id=CVE-2020-3830 Référence CVE CVE-2020-3831 https://www.cve.org/CVERecord?id=CVE-2020-3831 Référence CVE CVE-2020-3833 https://www.cve.org/CVERecord?id=CVE-2020-3833 R

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.
Fix not verified
Affected
n/a
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 29 Jan 2020 · Last source change 5 Aug 2024, 01:54 UTC · CWE-787 · Out-of-bounds Write

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-2019-8357
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
NVD statusNVD modified after enrichment

Core structured fields are present and their contributing authorities are shown above.

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
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-2019-18634 · cve.blacktree.nl