CVE-2026-44596

criticalpriority · attend · 50EPSS 0.021 · 81 %ileexploit · PoCEUUS
grimoire priorityP1 · Urgent
Exploitable?
Public exploit
2 exploits · PoC
Likely / severe?
2.06% (81st) EPSS
CVSS 9.8 · critical
Is it mine?
3 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

Yamcs is a mission control framework. Prior to 5.12.7, the authentication endpoint POST /auth/token in yamcs-core, handled by yamcs-core/src/main/java/org/yamcs/http/auth/AuthHandler.java, lacked any rate limiting, account lockout, or failed-attempt throttling, so an unauthenticated remote attacker could perform unlimited password-guessing attempts against any user account, significantly increasing the risk of successful brute-force attacks. This issue is fixed in versions 5.12.7 and 5.13.0.

01

cvss

Technical severity, 0–10. One row per scoring source.

9.8
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 6.5–9.8

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Nsecondary · ENISA EU
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Nsecondary · security-advisories@github.comexploitability 3.9 · impact 2.5
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Nsecondary · OSV
v3.19.3criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Psecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

04

exploits (2)

Public proof-of-concept and weaponised exploit code.

05

affected products (3)

Products and version ranges known to be affected.

06

advisories (1)

Vendor and ecosystem advisories describing this.

  • GHSA-w5r6-mcgq-7pq4Yamcs has No Rate Limiting on Authentication Endpoint2026-05-27ghsa · osvUS

    ### Summary The authentication endpoint `POST /auth/token` in `yamcs-core` lacks any form of rate limiting, account lockout, or failed attempt throttling. As a result, an unauthenticated remote attacker can perform unlimited password guessing attempts against any user account. This missing rate limiting vulnerability (CWE-307) significantly increases the risk of successful brute-force attacks. ### Root Cause **File:** `yamcs-core/src/main/java/org/yamcs/http/auth/AuthHandler.java` `POST /auth/token` has no rate limiting, no lockout after failed attempts, and no CAPTCHA. The handler processes unlimited authentication requests without any throttling mechanism: ```java // AuthHandler.java — handleToken() // No throttle, no failed attempt counter, no lockout private void handleToken(HandlerContext ctx) { ... getSecurityStore().login(token).whenComplete((info, err) -> { // Directly attempts authentication with no rate check }); } ``` This is absent by default — the official quickstart and documentation contain no guidance on configuring rate limiting. ### Impact An attacker can make unlimited authentication attempts against any account. This enables efficient brute-force attacks against any account. ### Proof of Concept ```bash # 20 attempts — zero rate limiting for i in $(seq 1 20); do curl -s -o /dev/null -w "Attempt $i: HTTP %{http_code}\n" \ -X POST "http://TARGET:8090/auth/token" \ -d "grant_type=password&username=operator&password=operator12$i" done # All return HTTP 401 — no HTTP 429 ever ``` **Confirmed:** 20 attempts in 0.07 seconds, no rate limiting enforced. ### Fix Implement DRF-style throttling on `/auth/token`: ```java // Track failed attempts per IP private static final Cache<String, Integer> FAILED_ATTEMPTS = CacheBuilder.newBuilder().expireAfterWrite(15, TimeUnit.MINUTES).build(); private static final int MAX_ATTEMPTS = 10; private void handleToken(HandlerContext ctx) { String ip = ctx.getRemoteAddress(); int attempts = Optional.ofNullable(FAILED_ATTEMPTS.getIfPresent(ip)).orElse(0); if (attempts >= MAX_ATTEMPTS) { throw new TooManyRequestsException("Rate limit exceeded"); } // ... existing auth logic // On failure: FAILED_ATTEMPTS.put(ip, attempts + 1) } ```

07

also known as (3)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

published 2026-07-16modified 2026-07-17
09

references (12)

External citations — patches, advisories, analysis.

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