Medium severity · published Oct 8, 2026
CVE-2026-107733
SumatraPDF: Null-pointer dereference in `CmdExec` when no document tab is open
6.8
CVSS
0.2%
EPSS
No
On KEV
Description
SumatraPDF is a multi-format reader for Windows. In 3.6.1 and earlier, FrameOnCommand() handles CmdExec by passing a null current-tab pointer to RunWithExe(), which dereferences WindowTab::filePath. A local process in the same interactive Windows session, at an integrity level greater than or equal to SumatraPDF's under Windows UIPI, can dispatch CmdExec over DDE or WM_COPYDATA while no document tab is open, causing abrupt process termination and loss of unsaved state. No broader impact is claimed beyond the advisory-supported conditions. No fixed version is available as of this review.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 5% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SU
sumatrapdf · sumatrapdfreader
<= 3.6.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-107733
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-107733
x_refsource_CONFIRM
https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-p2ph-2rvm-q37m
x_refsource_MISC
https://github.com/sumatrapdfreader/sumatrapdf/commit/013ad659c7de13fa15624d1f8a24e3231c50516b
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