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

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.

Published: 2025-06-26 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-52477 is rated Moderate Risk (52.6/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.28%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-52477

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-22 0.05% 0.28% +0.23%
2 2026-03-01 0.04% 0.05% +0.01%
3 2025-11-22 — 0.04% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-52477

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.6 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 4.0 [email protected]

Weakness enumeration for CVE-2025-52477

GitHub Security Advisory for CVE-2025-52477

GHSA-h3qp-hwvr-9xcq · Severity: high · Ecosystem: go — Octo STS Unauthenticated SSRF by abusing fields in OpenID Connect tokens

Affected software / configurations for CVE-2025-52477

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-52477

cvelogic Threat Intelligence