CVE-2021-39559
CVE-2021-39559 is a medium-severity vulnerability in Swftools with a CVSS 3.x base score of 5.5. 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-476.
Key facts
- Severity: Medium (CVSS 3.x base score 5.5)
- CVSS v2: 4.3
- EPSS exploit prediction: 1% (45th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-476
- Affected product: Swftools
- Published:
- Last modified:
Description
An issue was discovered in swftools through 20200710. A NULL pointer dereference exists in the function GString::~GString() located in GString.cc. It allows an attacker to cause Denial of Service.
Frequently asked questions
- What is CVE-2021-39559?
- An issue was discovered in swftools through 20200710. A NULL pointer dereference exists in the function GString::~GString() located in GString.cc. It allows an attacker to cause Denial of Service.
- How severe is CVE-2021-39559?
- CVE-2021-39559 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-39559 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-39559?
- CVE-2021-39559 affects Swftools. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-39559?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-39559 published?
- CVE-2021-39559 was published on 2021-09-20 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:swftools:swftools:*:*:*:*:*:*:*:*
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Browse all CWE-476 (NULL Pointer Dereference) vulnerabilities →