Medium severity · published Oct 8, 2026
CVE-2026-107730
SumatraPDF: Signed integer overflow in the LIT header parsing causes invalid-pointer read
5.5
CVSS
0.1%
EPSS
No
On KEV
Description
SumatraPDF is a multi-format reader for Windows. In 3.7.0.22298, LitParseHeader() in src/LitDoc.cpp computes the attacker-controlled hdrLen + nPieces * 16 section offset using signed 32-bit arithmetic without validating the complete result. When the component values make that aggregate calculation overflow to a negative value, pointer construction reaches an invalid read in LitU32(), causing deterministic application termination. The supplied evidence does not demonstrate code execution, information disclosure, arbitrary read, or integrity impact. No fixed version is available as of this review.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 2% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SU
sumatrapdf · sumatrapdfreader
<= 3.7.0.22298 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-107730
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-107730
x_refsource_CONFIRM
https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-vfpj-qhvj-92wg
x_refsource_MISC
https://github.com/sumatrapdfreader/sumatrapdf/commit/10a83278a5a6f67194dedfb67c47474d22ecfe4b
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