CVE-2026-53306tty: hvc_iucv: fix off-by-one in number of supported devices
- 5.5MediumCVSS base score
- 0.16%Exploitation in 30 daysEPSS · top 94% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: tty: hvc_iucv: fix off-by-one in number of supported devices MAX_HVC_IUCV_LINES == HVC_ALLOC_TTY_ADAPTERS == 8. This is the number of entries in: static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES]; Sometimes hvc_iucv_table[] is limited by: (a) if (num > hvc_iucv_devices) // for error detection or (b) for (i = 0; i < hvc_iucv_devices; i++) // in 2 places (so these 2 don't agree; second one appears to be correct to me.) hvc_iucv_devices can be 0..8. This is a counter. (c) if (hvc_iucv_devices > MAX_HVC_IUCV_LINES) If hvc_iucv_devices == 8, (a) allows the code to access hvc_iucv_table[8]. Oops.
Timeline
ID reserved
By Linux
- 17 days later
· 17 days later
Published
- 4 months later
· 4 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Analyzed | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.16% · top 94% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
- affected 44a01d5ba8a4d543694461cd3e178cfa6b3f221b – < 3d3b89e6ab93bdd0efd45828bda6b0e61cc46dff
- affected 44a01d5ba8a4d543694461cd3e178cfa6b3f221b – < 484357dff256c816d9466bda35eb765685e4dc86
- affected 44a01d5ba8a4d543694461cd3e178cfa6b3f221b – < 11207e42a332eb8bbcb9fe74df9edd2a807c5607
- affected 44a01d5ba8a4d543694461cd3e178cfa6b3f221b – < fed8b8f33a46db0ee2efdb000f4f630c86ed8ca4
- affected 44a01d5ba8a4d543694461cd3e178cfa6b3f221b – < a76511bc654819425d3b15e77b523d7f9d81f064
- affected 44a01d5ba8a4d543694461cd3e178cfa6b3f221b – < 3104a3f40feb107f77d7116ad9bf6c210ab7babf
- affected 44a01d5ba8a4d543694461cd3e178cfa6b3f221b – < f1dc8e72de9aabe5d96767a4e97219ac26b79fe5
- affected 44a01d5ba8a4d543694461cd3e178cfa6b3f221b – < f2a880e802ad12d1e38039d1334fb1475d0f5241
- affected 2.6.29
- unaffected < 2.6.29
- unaffected 5.10.258 – ≤ 5.10.*
- unaffected 5.15.209 – ≤ 5.15.*
- unaffected 6.1.175 – ≤ 6.1.*
- unaffected 6.6.141 – ≤ 6.6.*
- unaffected 6.12.91 – ≤ 6.12.*
- unaffected 6.18.33 – ≤ 6.18.*
- unaffected 7.0.10 – ≤ 7.0.*
- unaffected 7.1 – ≤ *
References
References8
- https://git.kernel.org/stable/c/3d3b89e6ab93bdd0efd45828bda6b0e61cc46dff (opens in a new tab)
- https://git.kernel.org/stable/c/484357dff256c816d9466bda35eb765685e4dc86 (opens in a new tab)
- https://git.kernel.org/stable/c/11207e42a332eb8bbcb9fe74df9edd2a807c5607 (opens in a new tab)
- https://git.kernel.org/stable/c/fed8b8f33a46db0ee2efdb000f4f630c86ed8ca4 (opens in a new tab)
- https://git.kernel.org/stable/c/a76511bc654819425d3b15e77b523d7f9d81f064 (opens in a new tab)
- https://git.kernel.org/stable/c/3104a3f40feb107f77d7116ad9bf6c210ab7babf (opens in a new tab)
- https://git.kernel.org/stable/c/f1dc8e72de9aabe5d96767a4e97219ac26b79fe5 (opens in a new tab)
- https://git.kernel.org/stable/c/f2a880e802ad12d1e38039d1334fb1475d0f5241 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-39841 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-53306)Record last updated .