PyMuPDF 1.25.3 before 2.0 contains a stack-based buffer overflow vulnerability in JM_set_annot_callout_line() that
Affects pymupdfSource GCVE Database
Not known to be exploited · CVSS 7.7 High.
Data as of 5 Nov 2026, 12:36 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 7.7 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 7.5 |
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 2 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10pymupdfpkg:deb/ubuntu/pymupdf?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSpymupdfpkg:deb/ubuntu/pymupdf?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSpymupdfpkg:deb/ubuntu/pymupdf?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSpymupdfpkg:deb/ubuntu/pymupdf?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSpymupdfpkg:deb/ubuntu/pymupdf?arch=source&distro=focalOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until a fix is confirmed, avoid processing untrusted input with affected PyMuPDF versions or apply any available updates to PyMuPDF 2.0 or later once released.
Description
PyMuPDF versions before 2.0, including several specific builds, contain a stack-based buffer overflow vulnerability in the JM_set_annot_callout_line() function. This flaw arises because the function copies a caller-supplied number of callout points into a fixed-size three-element stack array without proper bounds checking. An attacker controlling the callout argument to Page.add_freetext_annot() can supply four or more points, leading to stack frame overwrite, which may cause a crash or enable code execution.
References
- ubuntu.com/security/CVE-2026-120752 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-120752 (opens in a new tab)
- github.com/pymupdf/PyMuPDF/issues/5112 (opens in a new tab)
- github.com/pymupdf/PyMuPDF/issues/5173 (opens in a new tab)
- github.com/pymupdf/PyMuPDF (opens in a new tab)
- github.com/pymupdf/PyMuPDF/blob/1.28.2/src/extra.i (opens in a new tab)
- github.com/pymupdf/PyMuPDF/commit/d4298ead84ceeae1c9065c81cd9a275a1b092f5e (opens in a new tab)
- github.com/pymupdf/PyMuPDF/releases/tag/2.0 (opens in a new tab)
- vulncheck.com/advisories/pymupdf-1.25.3-before-2.0-stack-buffer-overflow-via-add-freetext-annot-callout (opens in a new tab)