Security Digest · Vulnerability record
CVE-2024-1735: Armeria SAML authentication bypass due to missing validation on unsigned SAML messages
A vulnerability has been identified in armeria-saml versions less than 1.27.2, allowing the use of malicious SAML messages to bypass authentication.
CVSS 9.1 Critical EPSS 0.8% · p57
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.8%, percentile 57: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 57% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
com.linecorp.armeria:armeria-saml(Maven) <= 1.27.1, fixed in 1.27.2. Check your lockfile, including transitive dependencies.
What it is
A vulnerability has been identified in armeria-saml versions less than 1.27.2, allowing the use of malicious SAML messages to bypass authentication. All users who rely on armeria-saml older than version 1.27.2 must upgrade to 1.27.2 or later.
From the GitHub advisory
Impact
The SAML implementation provided by armeria-saml currently accepts unsigned SAML messages (assertions, logout requests, etc.) as they are, rather than rejecting them by default. As a result, an attacker can forge a SAML message to authenticate themselves, despite the fact that such an unsigned SAML message should be rejected.
Patches
The vulnerability has been patched in Armeria version 1.27.2. All users who rely on armeria-saml older than version 1.27.2 must upgrade to 1.27.2 or later.
Workarounds
Weakness type: CWE-287, CWE-304.
Product: com.linecorp.armeria:armeria-saml (Maven) · Assigned by: LY-Corporation · Published: 2024-02-26
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| Maven | com.linecorp.armeria:armeria-saml | <= 1.27.1 | 1.27.2 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| LINE Corporation | Armeria | 0.69.0 < 1.27.2 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LY-Corporation | 3.1 | 9.1 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| GitHub | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.83% probability of exploitation activity in the next 30 days; percentile 57.
Timeline
- — CVE record published by LY-Corporation
- — GitHub-reviewed advisory GHSA-4m6j-23p2-8c54 published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-4m6j-23p2-8c54 github.com
- CVE.org record CVE-2024-1735 cve.org
- NVD entry CVE-2024-1735 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- github.com github.com
- github.com github.com
- github.com github.com