CVE-2026-24408 | sigstore has CSRF possibility in OIDC authentication during signing

sigstore-python is a Python tool for generating and verifying Sigstore signatures. Prior to version 4.2.0, the sigstore-python OAuth authentication flow is susceptible to Cross-Site Request Forgery. `_OAuthSession` creates a unique "state" and sends it as a parameter in the authentication request but the "state" in the server response seems not not be cross-checked with this value. Version 4.2.0 contains a patch for the issue.

Published: 2026-01-26 Last update: 2026-03-02 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-24408 is rated Low Risk (0.3/100): low exploitation likelihood (EPSS 0.01%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

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-2026-24408

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 2026-01-27 — 0.01% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-24408

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
0.0 3.1 NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 1.6 0.0 [email protected]
5.0 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L 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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 1.6 3.4 [email protected]

Weakness enumeration for CVE-2026-24408

GitHub Security Advisory for CVE-2026-24408

GHSA-hm8f-75xx-w2vr · Severity: low · Ecosystem: pip — sigstore CSRF possibility in OIDC authentication during signing

Affected software / configurations for CVE-2026-24408

Vendor Product Version Raw CPE
linuxfoundation sigstore-python < 4.2.0 cpe:2.3:a:linuxfoundation:sigstore-python:*:*:*:*:*:*:*:*

References for CVE-2026-24408

cvelogic Threat Intelligence