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TI-2026-81578 Aliases CVE-2026-58496

Out-of-bounds read in ThorVG SFNT/TTF font loader

Priority MEDIUM 53CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-125 and the CVSS impact.

Summary

ThorVG before 1.0.7 is affected. The SFNT/TTF font loader reads the first four bytes of input without first checking that the buffer holds at least four bytes (CWE-125). When an application loads a malformed short font directly from memory through public APIs such as tvg::Text::load, the read goes out of bounds, which may crash the application or disclose adjacent heap memory.

Written with Claude Haiku 5.5 from the sources below · 2026-11-02

Description from the CNA

Thor Vector Graphics (ThorVG) is a production-ready vector graphics engine. Prior to 1.0.7, the `SFNT/TTF` font loader's `SfntLoader::gen` function in `tvgSfntLoader.cpp` reads `data[0] through data[3]` to identify the font type without first checking that the input buffer contains at least four bytes. Loading an undersized font directly from memory through public APIs such as `tvg::Text::load` causes an out-of-bounds read. Loading through a file path using `mmap` can mask the read because of page alignment; the memory-loading API directly exposes it. Depending on memory layout, a malformed short font may crash the consuming application or disclose adjacent heap memory. This issue is fixed in version 1.0.7.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00211 11th percentileScored 2026-11-07
Fix Fixed thorvg (thorvg): 1.0.7

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
thorvgthorvgbefore 1.0.71.0.7Patch availableCNA
  • thorvg Vendorthorvg Affected before 1.0.7 Fixed in 1.0.7 Patch available CNA

Remediation

Update ThorVG to version 1.0.7, which fixes this issue.

Written with Claude Haiku 5.5 from the sources below · 2026-11-02

  • Fix · CNA thorvg (thorvg) Fixed in 1.0.7

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-27 Threatist record created from CVE-2026-58496
  2. 2026-10-30 Affected versions changed · Red Hat
  3. 2026-10-30 CVSS score added · Red Hat
  4. 2026-11-02 CISA SSVC decision points changed
  5. 2026-11-02 Priority changed: LOW → MEDIUM

References

Other 3

  • TI-2026-33467 ThorVG: Null pointer dereference in SVG loader causes crash via 6-byte malformed input CVSS 3.1MEDIUM 4.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences