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Fencer Intel
low 2.0

CVE-2026-123540 json

OpenAM before 16.1.4 Incomplete Attribute Encoding in SAML 1.x Form POST

published 21d ago modified yesterday also EUVD-2026-119425 , GHSA-pw99-8h4m-p3gm

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository OpenIdentityPlatform/OpenAM. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
2.0
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 8%
public exploits
0
none known

Summary

OpenAM before 16.1.4 contains an incomplete output encoding vulnerability that allows a SAML 1.x identity provider to alter attribute values by injecting unencoded content into the service provider auto-submitted form. Attackers controlling a trusted identity provider can craft assertion attribute names or values that reach the target application in modified form, undermining the integrity of received attributes.

Patch / fix

  • OpenIdentityPlatform OpenAM 16.1.4

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Exploit prediction

0.18% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 4.0 2.0 CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
CNA 3.1 2.0 CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:L/A:N
CNA 4.0 2.0 CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 2.0 CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:L/A:N

Affected products

  • OpenIdentityPlatform OpenAM

Classification

Weakness
  • CWE-116 Improper Encoding or Escaping of Output

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of OpenIdentityPlatform/OpenAM published their own advisory on GitHub. Reviewed sources take precedence over it.