Bug 2553667 (CVE-2026-102946)

Summary:	CVE-2026-102946 joserfc: joserfc: Signature verification bypass via empty signatures array
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	anpicker, anthomas, dfreiber, dkeler, drow, dschmidt, ebourniv, ehelms, ggainey, hasun, ikhan, ilpinto, jburrell, jfula, jlanda, jowilson, jpasqual, juwatts, jwong, kaycoth, kshier, ltomasbo, mdellweg, mhayden, mhulan, nmoumoul, nyancey, omaciel, ometelka, osousa, pcreech, ptisnovs, rbobbitt, rchan, rjohnson, sbunciak, sdoran, simaishi, smallamp, stcannon, suppawar, syedriko, thason, tmalecek, ttakamiy, vkumar, xdharmai, yguenane, ykashtan
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in joserfc. When processing a JSON Web Signature (JWS) in General JSON Serialization format, the library improperly treats tokens containing an empty signatures list as valid. A remote attacker without a valid signing key can exploit this flaw by submitting an arbitrary payload with an empty signatures array, bypassing signature verification and causing applications to treat untrusted data as authentic.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-10-15 18:42:01 UTC

joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. Prior to 1.7.4, joserfc.jws.deserialize_json() accepts a JWS General JSON Serialization with an empty signatures array as authenticated. The verify_general_json() loop performs no iterations for the empty array and returns success because no signature check failed, allowing an attacker without a signing key to supply an arbitrary payload that relying applications may treat as authentic. The issue affects the General JSON Serialization path; compact JWS and JWT decoding, Flattened JSON serialization, and JWE JSON processing do not follow this vulnerable path. This issue is fixed in version 1.7.4.