CVE-2026-22703 | Cosign verification accepts any valid Rekor entry under certain conditions

Exp

Cosign provides code signing and transparency for containers and binaries. Prior to versions 2.6.2 and 3.0.4, Cosign bundle can be crafted to successfully verify an artifact even if the embedded Rekor entry does not reference the artifact's digest, signature or public key. When verifying a Rekor entry, Cosign verifies the Rekor entry signature, and also compares the artifact's digest, the user's public key from either a Fulcio certificate or provided by the user, and the artifact signature to the Rekor entry contents. Without these comparisons, Cosign would accept any response from Rekor as valid. A malicious actor that has compromised a user's identity or signing key could construct a valid Cosign bundle by including any arbitrary Rekor entry, thus preventing the user from being able to audit the signing event. This issue has been patched in versions 2.6.2 and 3.0.4.

Published: 2026-01-10 Last update: 2026-02-05 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-22703 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.00%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2026-22703

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-22703

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 2026-01-10 — 0.00% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-22703

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
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:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 1.8 3.6 [email protected]
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
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:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2026-22703

GitHub Security Advisory for CVE-2026-22703

GHSA-whqx-f9j3-ch6m · Severity: medium · Ecosystem: go — Cosign verification accepts any valid Rekor entry under certain conditions

OS Trackers for CVE-2026-22703

vendor priority summary link
alpine — CVE-2026-22703: 1 source package rows (cosign); 24 state rows across 2 repos (3.23-community, edge-community); fixed 0, open 24. https://security.alpinelinux.org/vuln/CVE-2026-22703
debian not yet assigned CVE-2026-22703 not yet assigned priority: Debian including 1 source packages (cosign), 3 status rows across 3 suites (forky, sid, trixie): resolved 2, open 1. https://security-tracker.debian.org/tracker/CVE-2026-22703
redhat medium — https://access.redhat.com/security/cve/CVE-2026-22703
suse medium CVE-2026-22703 severity moderate: SUSE including 13 source package names (cosign-3.0.4-2.1, cosign-3.0.5-150400.3.35.1, …), 49 product×package rows across 38 product lines (Image SL-Micro, Image SL-Micro-Azure, … (38 product lines)): Fixed 46, Known Not Affected 2, First Fixed 1. https://www.suse.com/security/cve/CVE-2026-22703/
ubuntu medium CVE-2026-22703 medium priority: Ubuntu including 1 source packages (cosign), 5 status rows across 5 suites (jammy, noble, plucky, questing, upstream): DNE 2, needs-triage 2, ignored 1. https://ubuntu.com/security/CVE-2026-22703

Affected software / configurations for CVE-2026-22703

Vendor Product Version Raw CPE
sigstore cosign < 2.6.2 cpe:2.3:a:sigstore:cosign:*:*:*:*:*:*:*:*
sigstore cosign >= 3.0.0, < 3.0.4 cpe:2.3:a:sigstore:cosign:*:*:*:*:*:*:*:*

References for CVE-2026-22703

cvelogic Threat Intelligence