In sig_verify() in x509.c in axTLS version 2.1.3 and before, the PKCS#1 v1.5 signature verification blindly trusts the declared lengths in the ASN.1 structure
Published Nov 7, 2018
5.9
MEDIUMCVSS 3.0
EPSS 0.70%
Description
In sig_verify() in x509.c in axTLS version 2.1.3 and before, the PKCS#1 v1.5 signature verification blindly trusts the declared lengths in the ASN.1 structure. Consequently, when small public exponents are being used, a remote attacker can generate purposefully crafted signatures (and put them on X.509 certificates) to induce illegal memory access and crash the verifier.
Affected products
No data.
- ≤ 2.1.3
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
AV:N/AC:M/Au:N/C:N/I:N/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Table of values (11 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.70% (0.00696) | 51.28th | v5 (v2026.06.15) |
| Sep 20, 2026 | 0.70% (0.00696) | 51.57th | v5 (v2026.06.15) |
| Jul 20, 2024 | 0.19% (0.00189) | 56.77th | v3 (v2023.03.01) |
| Jun 26, 2024 | 0.19% (0.00189) | 56.59th | v3 (v2023.03.01) |
| Mar 30, 2024 | 0.18% (0.00178) | 54.18th | v3 (v2023.03.01) |
| Sep 3, 2023 | 0.19% (0.00193) | 56.32th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.24% (0.00236) | 59.89th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.05% (0.01055) | 52.13th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.05% (0.01055) | 27.52th | v2 (v2022.01.01) |
| Feb 3, 2022 | 0.78% (0.00785) | 22.12th | v5 (v2026.06.15) |
| Apr 14, 2021 | 0.78% (0.00785) | 0.00th | v1 |
References (2)
- https://github.com/igrr/axtls-8266/commit/5efe2947ab45e81d84b5f707c51d1c64be52f36c x_refsource_CONFIRMPatchThird Party Advisory
- https://sourceforge.net/p/axtls/mailman/message/36459928/ mailing-listx_refsource_MLISTExploitPatchThird Party Advisory
| Link | Providers | Tags |
|---|---|---|
| https://github.com/igrr/axtls-8266/commit/5efe2947ab45e81d84b5f707c51d1c64be52f36c | x_refsource_CONFIRMPatchThird Party Advisory | |
| https://sourceforge.net/p/axtls/mailman/message/36459928/ | mailing-listx_refsource_MLISTExploitPatchThird Party Advisory |
Change history (0)
No recorded changes yet.