Out-of-Bounds Write Vulnerability in CFITSIO by HEASARC
CVE-2026-115504

8.5HIGH

Key Information:

Vendor

Heasarc

Status
Cfitsio
Vendor
CVE Published:
22 October 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-115504?

CFITSIO, up to version 4.7.0, possesses a vulnerability in the ffgcls2() function found in getcols.c. The vulnerability occurs due to incorrect handling of attacker-supplied heap descriptor lengths for variable-length string columns, leading to an out-of-bounds write condition. By crafting a malicious FITS file, an attacker can exploit this flaw to overflow a fixed 28,800-byte stack buffer, potentially gaining the ability to execute arbitrary code within the context of the application.

Affected Version(s)

cfitsio 0 <= 4.7.0

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-115504 - Proof of Concept

References

https://gist.github.com/yure1432/98f15c7e8f48dc90ae65646f...
technical-descriptionexploit
https://github.com/HEASARC/cfitsio/pull/184
patchissue-tracking
https://github.com/HEASARC/cfitsio/commit/579792e0f85bff0...
patch

CVSS V4

Score:
8.5
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Pratyaksh Srivats
.