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Full vulnerability report · 2026
CVE-2026-55618High confidence

eml_parser: URL extraction bypass via HTML entities in URLs

GOVCERT-LU · eml parser

Official source article: GitHub GHSA-FXGQ-9M89-CXJ9 ↗. Check the applicable product and release in the original source.

6.5MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • EPSS is 0.52% 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 GOVCERT-LU eml parser 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: As exposure requiresRemediation target: Within 365 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.

Open-source package ranges3 source-attributed ranges

These OSV and GitHub advisory ranges apply only to the named package and ecosystem. A listed fixed version is not a universal product patch or proof that an update is installed.

Ecosystem and packageAffected rangeFirst fixed versionEvidence
PyPIeml-parserECOSYSTEM: introduced 0; fixed 3.0.23.0.2OSV record ↗aggregator derived · 10 Sep 2026
PyPIeml-parserECOSYSTEM: introduced 0; fixed 3.0.23.0.2OSV record ↗source linked ecosystem record · 10 Sep 2026
pipeml_parser< 3.0.23.0.2GitHub advisory ↗upstream repository advisory · 25 Aug 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-2026-55618 · CSAF 2.0 · revision 3 · finalRed Hat Product Securityeml_parser: eml_parser: Security bypass due to incorrect URL validation
1 known not affected

The vendor explicitly states that these products are not affected by this CVE.

  • All currently supported Red Hat products
Summary
A flaw was found in eml_parser, a Python module for parsing email files. The `clean_found_uri` function incorrectly validates Uniform Resource Locator (URL) strings by processing them before unescaping HTML entities. This allows a remote attacker to craft malicious URLs using HTML entities that are then improperly rejected and omitted from extracted URL lists. Consequently, email security gateways and Security Operations Center (SOC) pipelines may fail to detect and inspect these hidden malicious links, leading to a bypass of security measures and potential information disclosure.
Remediation
No remediation text is recorded.
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-2026-65697

No EUVD known-exploited evidence

eml_parser serves as a python module for parsing eml files and returning various information found in the e-mail as well as computed information. Prior to 3.0.2, the clean_found_uri function in eml_parser/parser.py validates potential URL strings before unescaping HTML entities used for colon, slash, or period characters. Valid encoded URLs and their host names are therefore rejected and omitted from the extracted URL and domain lists. Email security gateways and SOC pipelines that use those lists as indicators of compromise may fail to submit the hidden URLs to threat intelligence feeds, reputation services, or sandboxes, allowing malicious links to bypass inspection. This issue is fixed in version 3.0.2.

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
6.5 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

eml_parser serves as a python module for parsing eml files and returning various information found in the e-mail as well as computed information. Prior to 3.0.2, the clean_found_uri function in eml_parser/parser.py validates potential URL strings before unescaping HTML entities used for colon, slash, or period characters. Valid encoded URLs and their host names are therefore rejected and omitted from the extracted URL and domain lists. Email security gateways and SOC pipelines that use those lists as indicators of compromise may fail to submit the hidden URLs to threat intelligence feeds, reputation services, or sandboxes, allowing malicious links to bypass inspection. This issue is fixed in version 3.0.2.

What

eml_parser serves as a python module for parsing eml files and returning various information found in the e-mail as well as computed information. Prior to 3.0.2, the clean_found_uri function in eml_parser/parser.py validates potential URL strings before unescaping HTML entities used for colon, slash, or period characters. Valid encoded URLs and their host names are therefore rejected and omitted from the extracted URL and domain lists. Email security gateways and SOC pipelines that use those lists as indicators of compromise may fail to submit the hidden URLs to threat intelligence feeds, reputation services, or sandboxes, allowing malicious links to bypass inspection. This issue is fixed in version 3.0.2.

Why

The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.

How

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

What

eml_parser serves as a python module for parsing eml files and returning various information found in the e-mail as well as computed information. Prior to 3.0.2, the clean_found_uri function in eml_parser/parser.py validates potential URL strings before unescaping HTML entities used for colon, slash, or period characters. Valid encoded URLs and their host names are therefore rejected and omitted from the extracted URL and domain lists. Email security gateways and SOC pipelines that use those lists as indicators of compromise may fail to submit the hidden URLs to threat intelligence feeds, reputation services, or sandboxes, allowing malicious links to bypass inspection. This issue is fixed in version 3.0.2.

Why

The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.

How

An attacker operating through a network path may attempt exploitation without authentication after a 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 → Improper Encoding or Escaping of Output → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
Required interaction required
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-116 ↗

CWE-116: Improper Encoding or Escaping of Output. The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.

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:R/S:U/C:N/I:H/A:N

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.UIRequiredUser interaction: Another user must perform an action for exploitation to succeed.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.IHighIntegrity impact: A successful attack can cause a major loss.ANoneAvailability impact: No direct loss is represented by this metric.
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-116
A

Official authority intelligence

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

ENISA EUVD · EUVD-2026-65697Official EUVD mapping

eml_parser serves as a python module for parsing eml files and returning various information found in the e-mail as well as computed information. Prior to 3.0.2, the clean_found_uri function in eml_parser/parser.py validates potential URL strings before unescaping HTML entities used for colon, slash, or period characters. Valid encoded URLs and their host names are therefore rejected and omitted from the extracted URL and domain lists. Email security gateways and SOC pipelines that use those lists as indicators of compromise may fail to submit the hidden URLs to threat intelligence feeds, reputation services, or sandboxes, allowing malicious links to bypass inspection. This issue is fixed in version 3.0.2.

Official EUVD record ↗
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
eml parser: < 3.0.2
Fixed
3.0.2.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
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 25 Aug 2026 · Last source change 28 Aug 2026, 22:31 UTC · CWE-116 · Improper Encoding or Escaping of Output

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-26
European sourceENISA EUVD · EUVD-2026-65697
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD not scheduled

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

Material change intelligence

What changed after publication

View recent updates ↗
  1. ENISA EUVD mappingEUVD-2026-65697 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2026-65697"}
    ENISA EUVD ↗
  2. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
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-2026-55618 · cve.blacktree.nl