8.6

CVE-2025-52477: Octo-STS Vulnerable to Unauthenticated SSRF with HTTP Response Reflection in OIDC Flow

Deferred
AliasesCGA-79hx-qg38-7crqCGA-8p3f-546v-p7f6CGA-mfwf-v9mj-hpwf
Published 26-06-2025Last modified 27-06-2025

Vulnerability summary

CVE-2025-52477 is a high (CVSS 8.6) Server-Side Request Forgery vulnerability in octo-sts app. EPSS estimates a 0.49% chance of exploitation in the next 30 days, higher than 41.9% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 8.6 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 0% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
8.6/10
010
High · v3.1 (CVE.org)
EPSS score
0.49%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1 · Related 3
OPENSUSE-SU-2025:15405-1CGA-R6MM-WMG3-7MRRCGA-W4GX-3PPV-4XX2

Timeline

  1. 26-06-2025
    PublishedVulnerability first disclosed.
  2. 27-06-2025
    Last modifiedVulnerability information updated.

Description

Octo-STS is a GitHub App that acts like a Security Token Service (STS) for the GitHub API. Octo-STS versions before v0.5.3 are vulnerable to unauthenticated SSRF by abusing fields in OpenID Connect tokens. Malicious tokens were shown to trigger internal network requests which could reflect error logs with sensitive information. Upgrade to v0.5.3 to resolve this issue. This version includes patch sets to sanitize input and redact logging.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.49%

Chance of exploitation in the next 30 days

Percentile

42%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.49% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Chainguard2 products
  • octo-sts< 0.5.3-r0
  • octo-sts-webhook< 0.5.3-r0
Wolfi2 products
  • octo-sts< 0.5.3-r0
  • octo-sts-webhook< 0.5.3-r0
Github.com/octo-sts1 product
  • app< 0.5.3
Octo-sts1 product

4 vendors · 6 products

References

6 links