What is the CVSS score of CVE-2017-17821?

CVE-2017-17821 has a CVSS 3.0 base score of 9.8 (Critical). CVSS vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.7%.

Is there a public PoC exploit available for CVE-2017-17821?

Yes, a public proof-of-concept exploit is available for CVE-2017-17821. Prioritise patching immediately. EPSS: 0.7%.

Safari CVE-2017-17821

CRITICAL

Buffer Overflow (CWE-119)

2017-12-21 cve@mitre.org

Buffer Overflow Denial Of Service Apple Safari

9.8

CVSS 3.0 · NVD

Severity by source

NVD PRIMARY

9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

CVE Published

Dec 21, 2017 - 03:29 cve.org

CRITICAL 9.8

DescriptionCVE.org

WTF/wtf/FastBitVector.h in WebKit, as distributed in Safari Technology Preview Release 46, allows remote attackers to cause a denial of service (buffer overflow) or possibly have unspecified other impact because it calls the FastBitVectorWordOwner::resizeSlow function (in WTF/wtf/FastBitVector.cpp) for a purpose other than initializing a bitvector size, and resizeSlow mishandles cases where the old array length is greater than the new array length.

AnalysisAI

WTF/wtf/FastBitVector.h in WebKit, as distributed in Safari Technology Preview Release 46, allows remote attackers to cause a denial of service (buffer overflow) or possibly have unspecified other. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.

Technical ContextAI

This vulnerability is classified as Buffer Overflow (CWE-119), which allows attackers to corrupt memory to execute arbitrary code or crash the application. WTF/wtf/FastBitVector.h in WebKit, as distributed in Safari Technology Preview Release 46, allows remote attackers to cause a denial of service (buffer overflow) or possibly have unspecified other impact because it calls the FastBitVectorWordOwner::resizeSlow function (in WTF/wtf/FastBitVector.cpp) for a purpose other than initializing a bitvector size, and resizeSlow mishandles cases where the old array length is greater than the new array length. Affected products include: Apple Safari.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Use memory-safe languages or bounds-checking. Enable ASLR, DEP/NX, stack canaries. Use safe string functions.