CVE-2026-23951— SumatraPDF's Integer Underflow in PalmDbReader Leads to Crash
Quick assessment
Affected
sumatrapdfreader sumatrapdf
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
sumatrapdf是sumatrapdfreader开源的一个PDF阅读器。 SumatraPDF存在数字错误漏洞，该漏洞源于处理特制Mobi文件时存在差一错误和整数下溢，可能导致越界堆读取和应用程序崩溃。
Possible ATT&CK Techniques 1 AI
T1203 · Exploitation for Client Execution
Get alerts for future matching vulnerabilities
Log in to subscribe
I. Basic Information for CVE-2026-23951
Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗
Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.
Vulnerability Title
SumatraPDF's Integer Underflow in PalmDbReader Leads to Crash
Source: CVE Program / CVE List V5
Vulnerability Description
SumatraPDF is a multi-format reader for Windows. All versions contain an off-by-one error in the validation code that only triggers with exactly 2 records, causing an integer underflow in the size calculation. This bug exists in PalmDbReader::GetRecord when opening a crafted Mobi file, resulting in an out-of-bounds heap read that crashes the app. There are no published fixes at the time of publication.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
跨界内存读
Source: CVE Program / CVE List V5
Vulnerability Title
sumatrapdf 数字错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
sumatrapdf是sumatrapdfreader开源的一个PDF阅读器。 SumatraPDF存在数字错误漏洞，该漏洞源于处理特制Mobi文件时存在差一错误和整数下溢，可能导致越界堆读取和应用程序崩溃。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| sumatrapdfreader | sumatrapdf | <= 3.5.2rel | - |
|
II. Public POCs for CVE-2026-23951
| # | POC Description | Source Link | Shenlong Link |
|---|
AI-Generated POC
Premium
No public POC found.
Login to generate AI POCIII. Intelligence Information for CVE-2026-23951
请登录查看更多情报信息。
IV. Related Vulnerabilities
Same product: sumatrapdf
-
CVE-2026-55586
SumatraPDF: Heap out-of-bounds write in vendored CHMLib LZX -
CVE-2026-25961
SumatraPDF Update MITM -> Arbitrary Code Execution -
CVE-2026-25920
SumatraPDF has a heap out-of-bounds read in MOBI HuffDic dec -
CVE-2026-25880
Untrusted Search Path in SumatraPDF Reader (explorer.exe on -
CVE-2026-23512
SumatraPDF has an Untrusted Search Path in sumatrapdf/src/Ap
Same vendor: sumatrapdfreader
-
CVE-2026-55586
SumatraPDF: Heap out-of-bounds write in vendored CHMLib LZX -
CVE-2026-25961
SumatraPDF Update MITM -> Arbitrary Code Execution -
CVE-2026-25920
SumatraPDF has a heap out-of-bounds read in MOBI HuffDic dec -
CVE-2026-25880
Untrusted Search Path in SumatraPDF Reader (explorer.exe on -
CVE-2026-23512
SumatraPDF has an Untrusted Search Path in sumatrapdf/src/Ap
Same weakness: CWE-125
-
CVE-2026-16782
SVG File Parsing Out-of-Bounds Read Vulnerability in Autodes -
CVE-2026-78475
Gimp: unbounded stack vla and 21-byte stack over-read in pix -
CVE-2026-78157
Open5GS Rx AA-Request pcrf-rx-path.c pcrf_rx_aar_cb out-of-b -
CVE-2026-78049
Systerel S2OPC AddNodes Service sopc_node_mgt_helper_interna -
CVE-2026-54789
mod_auth_openidc has out-of-bounds read and write in state c
V. Comments for CVE-2026-23951
No comments yet