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CVE-2026-125756

8.2 highFix available

High (8.2) in postalsys postal-mime.

On this page
postal-mime before 4.2.1 contains a parser differential vulnerability in its address parser that truncates the domain at folding whitespace or comments preceding a dot. Remote attackers can craft From headers that pass SPF/DKIM/DMARC alignment for their own subdomain while PostalMime.parse() reports a spoofed victim sender address.

Severity

CVSS 4.0

8.2 high
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS 3.1

5.9 medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE
CWE-436 Interpretation Conflict
OWASP Top 10
A06:2025 Insecure Design
Published
Assigned by
VulnCheck (CNA)
NVD analysis
Not in the NVD yet
Record from
the CVE List, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
postalsys postal-mimebefore 4.2.1

Attack patterns (CAPEC)

  • CAPEC-34 HTTP Response Splitting Likelihood: Medium · Severity: High
  • CAPEC-105 HTTP Request Splitting Likelihood: Medium · Severity: High
  • CAPEC-273 HTTP Response Smuggling Likelihood: Medium · Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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