CVE-2026-81879

radare2: Heap out-of-bounds read in radare2 ELF PN_XNUM handling

MEDIUM
6.1
CVSS Score
Published: September 22, 2026 at 03:09 PM UTC
Updated: September 25, 2026 at 05:07 PM UTC
2 products affected across 2 vendorsRADARE2RADARE2

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Severity
MEDIUM6.1
Exploit prediction
EPSS 0.2%
SSVC
PoC

Description

radare2 is a UNIX-like reverse engineering framework and command-line toolset. Prior to 6.2.0, radare2's ELF PN_XNUM handling was vulnerable because the ELF parser allocated the program-header array using the resolved PN_XNUM count but several consumers still iterated with the original e_phnum value of 65535. The vulnerability is triggered by processing a crafted ELF file with e_phnum = 0xffff and a much smaller resolved count in shdr[0].sh_info. Consumers iterated beyond the allocated program-header array. This can cause a heap out-of-bounds read and process termination, resulting in denial of service; memory disclosure and code execution have not been demonstrated. This issue is fixed in version 6.2.0.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 6.2.0
Affected range stops below 6.2.0, so it looks safe — our inference, not a vendor statement
v < 6.2.0
Affected range stops below 6.2.0, so it looks safe — our inference, not a vendor statement

References (5)

x_refsource_CONFIRMPatchVendor Advisory
Source: cverecord
https://github.com/radareorg/radare2/security/advisories/GHSA-jqfq-hvcp-xh4p
x_refsource_MISCExploitIssue TrackingMitigationVendor Advisory
Source: cverecord
https://github.com/radareorg/radare2/issues/26223
x_refsource_MISCPatch
Source: cverecord
https://github.com/radareorg/radare2/pull/26178
x_refsource_MISCRelease Notes
Source: cverecord
https://github.com/radareorg/radare2/releases/tag/6.2.0

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-125

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