CVE-2019-13628 json
wolfCrypt leaks cryptographic information via timing side channel
published 2019-10-03 7 y ago modified 2026-07-07 4 mo ago also GHSA-q95h-vc86-hv77 , PYSEC-2026-1066 , EUVD-2022-4925
- cvss
- 4.7
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 32%
- public exploits
- 0
- none known
Summary
wolfSSL and wolfCrypt 4.0.0 and earlier (when configured without --enable-fpecc, --enable-sp, or --enable-sp-math) contain a timing side channel in ECDSA signature generation. This allows a local attacker, able to precisely measure the duration of signature operations, to infer information about the nonces used and potentially mount a lattice attack to recover the private key used. The issue occurs because ecc.c scalar multiplication might leak the bit length.
Patch / fix
- pypi wolfcrypt 4.1.0
- wolfssl Debian 13, Debian 12 4.1.0+dfsg-1
debian advisories DEBIAN-CVE-2019-13628
Exploit prediction
0.38% chance of exploitation in the next 30 days, higher than 32% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N |
| NVD | 2.0 | 1.2 | AV:L/AC:H/Au:N/C:P/I:N/A:N |
| OSV | 3.1 | 4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N |
| GitHub | 3.1 | 4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | wolfcrypt | <4.1.0 |
4.1.0 |
Classification
- Weakness
-
- CWE-203 Observable Discrepancy
References
-
eprint.iacr.org
/2011/232.pdf
web, technical-description, third-party-advisory
-
tches.iacr.org
/index.php/TCHES/article/view/7337
web, technical-description, third-party-advisory
-
openwall.com
/lists/oss-security/2019/10/02/2
mailing-list, web, third-party-advisory
-
minerva.crocs.fi.muni.cz
/
product
-
nvd.nist.gov
/vuln/detail/CVE-2019-13628
advisory
-
github.com
/wolfSSL/wolfcrypt-py
package
-
minerva.crocs.fi.muni.cz
web
-
pypi.org
/project/wolfcrypt
package
-
github.com
/advisories/GHSA-q95h-vc86-hv77
advisory
Sources
- CVE List CVE-2019-13628
- GitHub Advisory GHSA-q95h-vc86-hv77
- NVD CVE-2019-13628
- OSV PYSEC-2026-1066
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.