CVE-2026-49206 json
rapidcsv: Integer overflow in iterator arithmetic causes out-of-bounds access
published 4mo ago modified 26d ago also EUVD-2026-101286 , GHSA-v83v-8j5q-6553
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository d99kris/rapidcsv. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 2.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 4%
- public exploits
- 0
- none known
Summary
rapidcsv is a C++ CSV parser library. Prior to 8.99, RemoveColumn, InsertColumn, RemoveRow, InsertRow, and GetColumnNames converted size_t indexes to int before adding them to std::vector iterators. On 64-bit systems, in a CSV matrix dimension containing more than 2^31 elements, an index above INT_MAX could wrap to a negative iterator offset and point before the start of the vector, causing undefined behavior, heap memory corruption, or a crash. Triggering the issue requires an extremely large in-memory document, requiring tens of gigabytes of memory at minimum, so typical CSV documents are not practically affected. This issue is fixed in version 8.99.
Patch / fix
Is CVE-2026-49206 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 27d ago
Exploit prediction
0.16% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 2.9 | CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L |
Affected products
- d99kris rapidcsv
Classification
References
Sources
- CVE List CVE-2026-49206
- NVD CVE-2026-49206
- Maintainer advisory GHSA-v83v-8j5q-6553
Fencer Intel 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.
The maintainers of d99kris/rapidcsv published their own advisory on GitHub. Reviewed sources take precedence over it.