CVE-2021-39534
CVE-2021-39534 is a high-severity vulnerability in Juniper Libslax with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v2: 6.8
- EPSS exploit prediction: 1% (64th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Juniper Libslax
- Published:
- Last modified:
Description
An issue was discovered in libslax through v0.22.1. slaxIsCommentStart() in slaxlexer.c has a heap-based buffer overflow.
Frequently asked questions
- What is CVE-2021-39534?
- An issue was discovered in libslax through v0.22.1. slaxIsCommentStart() in slaxlexer.c has a heap-based buffer overflow.
- How severe is CVE-2021-39534?
- CVE-2021-39534 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-39534 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-39534?
- CVE-2021-39534 affects Juniper Libslax. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-39534?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-39534 published?
- CVE-2021-39534 was published on 2021-09-20 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:juniper:libslax:*:*:*:*:*:*:*:*
More vulnerabilities in Juniper Libslax
- CVE-2021-39533 — High (CVSS 8.8): An issue was discovered in libslax through v0.22.1. slaxLexer() in slaxlexer.c has a heap-based buffer overflow.
- CVE-2021-39531 — High (CVSS 8.8): An issue was discovered in libslax through v0.22.1. slaxLexer() in slaxlexer.c has a stack-based buffer overflow.
- CVE-2021-39532 — Medium (CVSS 6.5): An issue was discovered in libslax through v0.22.1. A NULL pointer dereference exists in the function slaxLexer()…
- CVE-2019-1010232 — Medium (CVSS 6.5): Juniper juniper/libslax libslax latest version (as of commit 084ddf6ab4a55b59dfa9a53f9c5f14d192c4f8e5 Commits on Sep 1,…
All CVEs affecting Juniper Libslax →
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