CVE-2026-13089
OIDC::Lite versions through 0.12.1 for Perl allow ID Token signature verification bypass via a token-controlled algorithm allowlist in verify
Published Jul 22, 2026
CVSS 3.1 · 7.5 High
EPSS < 1%
KEV · Not listed
Description
OIDC::Lite versions through 0.12.1 for Perl allow ID Token signature verification bypass via a token-controlled algorithm allowlist in verify.
When the caller does not pin an algorithm, OIDC::Lite::Model::IDToken::verify sets $self->alg($self->header->{alg}) from the token's own header and then calls decode_jwt(token, key, 1, [$self->alg]), handing JSON::WebToken an accepted-algorithm allowlist taken from the untrusted token. A token with alg=none yields ['none'], so decode_jwt returns the claims with no signature check, and a token with alg=HS256 is verified with the RP's RSA public key as the HMAC secret (RS to HS confusion).
The ID Token is the OpenID Connect authentication assertion delivered to the Relying Party. Any caller that verifies an ID Token through the unpinned load(token)->verify path, or load(token, key) with only the key pinned, accepts a forged token carrying attacker-chosen claims such as sub and is authenticated as any user. Passing an explicit algorithm so $self->alg is already set bypasses the header-derived allowlist and is not affected.
Note that the latest version uploaded to CPAN is 0.10. Later versions are available in the git repository.
When the caller does not pin an algorithm, OIDC::Lite::Model::IDToken::verify sets $self->alg($self->header->{alg}) from the token's own header and then calls decode_jwt(token, key, 1, [$self->alg]), handing JSON::WebToken an accepted-algorithm allowlist taken from the untrusted token. A token with alg=none yields ['none'], so decode_jwt returns the claims with no signature check, and a token with alg=HS256 is verified with the RP's RSA public key as the HMAC secret (RS to HS confusion).
The ID Token is the OpenID Connect authentication assertion delivered to the Relying Party. Any caller that verifies an ID Token through the unpinned load(token)->verify path, or load(token, key) with only the key pinned, accepts a forged token carrying attacker-chosen claims such as sub and is authenticated as any user. Passing an explicit algorithm so $self->alg is already set bypasses the header-derived allowlist and is not affected.
Note that the latest version uploaded to CPAN is 0.10. Later versions are available in the git repository.
Affected Products
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CVE record
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NVD configurations
No data
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Red Hat packages
No data
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OpenCVE enrichment
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
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| RITOU | OIDC::Lite | unaffected |
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No data.
No data.
| Vendor | Product | Versions | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Ritou | Oidc::lite |
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Remediation
Vendor Workaround
Apply the patch. Otherwise, pin the expected signature algorithm at the call site, for example OIDC::Lite::Model::IDToken->load($token, $key, $alg) with an explicit non-none $alg, so verify uses the pinned algorithm instead of the value in the token header.
Tracking
Advisories
Metrics
No CVSS v4.0
Attack Vector Network
Attack Complexity Low
Privileges Required None
Scope Unchanged
Confidentiality Impact None
Integrity Impact High
Availability Impact None
User Interaction None
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.369% probability within 30 days)
Exploitation none
Automatable yes
Technical Impact partial
References
History
Jul 27, 2026 8:30 PM
Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
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| Metrics |
cvssV3_1
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Jul 23, 2026 9:45 PM
First appearance in the feed. Affected vendors updated
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| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Ritou
Ritou oidc::lite |
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| Vendors & Products |
Ritou
Ritou oidc::lite |
Jul 22, 2026 9:00 PM
Description updated. Title updated. Weaknesses updated. Added references
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Description | OIDC::Lite versions through 0.12.1 for Perl allow ID Token signature verification bypass via a token-controlled algorithm allowlist in verify. When the caller does not pin an algorithm, OIDC::Lite::Model::IDToken::verify sets $self->alg($self->header->{alg}) from the token's own header and then calls decode_jwt(token, key, 1, [$self->alg]), handing JSON::WebToken an accepted-algorithm allowlist taken from the untrusted token. A token with alg=none yields ['none'], so decode_jwt returns the claims with no signature check, and a token with alg=HS256 is verified with the RP's RSA public key as the HMAC secret (RS to HS confusion). The ID Token is the OpenID Connect authentication assertion delivered to the Relying Party. Any caller that verifies an ID Token through the unpinned load(token)->verify path, or load(token, key) with only the key pinned, accepts a forged token carrying attacker-chosen claims such as sub and is authenticated as any user. Passing an explicit algorithm so $self->alg is already set bypasses the header-derived allowlist and is not affected. Note that the latest version uploaded to CPAN is 0.10. Later versions are available in the git repository. | |
| Title | OIDC::Lite versions through 0.12.1 for Perl allow ID Token signature verification bypass via a token-controlled algorithm allowlist in verify | |
| Weaknesses | CWE-347 | |
| References |
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Subscriptions
Weaknesses
