How severe is CVE-2015-8853?

CVE-2015-8853 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2015-8853 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-8853?

CVE-2015-8853 primarily affects Perl. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2015-8853?

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-2015-8853 published?

CVE-2015-8853 was published on 2016-05-25 and last updated on 2026-06-17.

CVE-2015-8853

CVE-2015-8853 is a high-severity vulnerability in Perl with a CVSS 3.x base score of 7.5. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Perl
Published: 2016-05-25
Last modified: 2026-06-17

Description

The (1) S_reghop3, (2) S_reghop4, and (3) S_reghopmaybe3 functions in regexec.c in Perl before 5.24.0 allow context-dependent attackers to cause a denial of service (infinite loop) via crafted utf-8 data, as demonstrated by "a\x80."

Frequently asked questions

What is CVE-2015-8853?: The (1) S_reghop3, (2) S_reghop4, and (3) S_reghopmaybe3 functions in regexec.c in Perl before 5.24.0 allow context-dependent attackers to cause a denial of service (infinite loop) via crafted utf-8 data, as demonstrated by "a\x80."
How severe is CVE-2015-8853?: CVE-2015-8853 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2015-8853 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-8853?: CVE-2015-8853 primarily affects Perl. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2015-8853?: 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-2015-8853 published?: CVE-2015-8853 was published on 2016-05-25 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:fedoraproject:fedora:22:*:*:*:*:*:*:*
cpe:2.3:a:perl:perl:*:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

182.93.50.90 (ipv4-addr)
103.165.139.145 (ipv4-addr)
121.40.151.192 (ipv4-addr)
40.83.182.122 (ipv4-addr)