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Fencer Vulns
medium 5.5

CVE-2026-88050 json

Tesseract: Out-of-bounds write in UnicharCompress via unvalidated recoder code values

published 2026-09-10 1 mo ago modified 2026-09-14 55 d ago also EUVD-2026-75593

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 4%
public exploits
0
none known

Summary

Tesseract is an open source OCR engine. In version 5.5.3 and earlier, RecodedCharID::DeSerialize in src/ccutil/unicharcompress.h validates length_ but accepts negative code_ values from a crafted .traineddata recoder component. UnicharCompress::ComputeCodeRange in src/ccutil/unicharcompress.cpp can consequently produce code_range_ equal to zero, after which SetupDecoder indexes is_valid_start_ with the negative code on a size-zero vector. The resulting out-of-bounds bit write uses a large wrapped index and reliably causes a wild-address crash or allocation failure on the default LSTM engine. No fixed release is available as of this review.

Patch / fix

  • tesseract Ubuntu Pro 18.04 LTS 4.00~git2288-10f4998a-2ubuntu0.1~esm1
  • tesseract Ubuntu Pro 20.04 LTS 4.1.1-2ubuntu0.1~esm1
  • tesseract Ubuntu Pro 22.04 LTS 4.1.1-2.1ubuntu0.1~esm1
  • tesseract Ubuntu Pro 24.04 LTS 5.3.4-1ubuntu0.1~esm1
  • tesseract Ubuntu Pro 26.04 LTS 5.5.0-1ubuntu0.1~esm1

ubuntu advisories UBUNTU-CVE-2026-88050

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • tesseract-ocr openSUSE Leap 16.0 5.5.3-bp160.1.1
  • tesseract-ocr openSUSE Tumbleweed 5.5.3-2.1

opensuse advisories openSUSE-SU-2026:21957-1openSUSE-SU-2026:11887-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-88050 updated cvss 5.5

tesseract: Tesseract: Out-of-bounds write leads to Denial of Service

  • Red Hat Enterprise Linux 8 tesseract, tesseract 5.3.4-7.el10_2 Red Hat Enterprise Linux 9 tesseract, tesseract 5.3.4-7.el10_2 Red Hat Enterprise Linux 10 tesseract 5.3.4-7.el10_2
    affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
59 d ago

Exploit prediction

0.15% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/tesseract-ocr/tesseract/security/advisories/GHSA-7v9h-3q3m-w68g referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 6.9 CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CNA 4.0 6.9 CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • tesseract-ocr tesseract

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.