CVE-2017-7246: Stack-based buffer overflow in the pcre32_copy_substring function in pcre_get.c in libpcre1 in PCRE 8.40 allow

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HIGH 7.8DOWNGRADE

CVE-2017-7246 is a high-severity flaw (CVSS 7.8) affecting pcre. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Stack-based buffer overflow in the pcre32_copy_substring function in pcre_get.c in libpcre1 in PCRE 8.40 allows remote attackers to cause a denial of service (WRITE of size 268) or possibly have unspecified other impact via a crafted file.

Why this priority

High severity

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	7.8 (High)
Attack vector	Local
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	2.6% (top 15%)
CISA exploited list	No
Weakness	CWE-119
Published	2017-03-23
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: pcre

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2017-03-23 21:59 UTCPublished CVE record published
2026-06-17 01:23 UTCUpdated Record last modified

pcre pcre DOWNGRADE

Affected: 8.40

Fixed in: no fixed release known

Safe to downgrade to: a release before 8.40

1. Check installed version

apt-cache policy pcre || rpm -q pcre || pcre --version

2. No fixed release: DOWNGRADE to a release before 8.40 (Debian / Ubuntu)

apt-cache madison pcre sudo apt install pcre=<VERSION_BEFORE_8.40> sudo apt-mark hold pcre

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list pcre sudo dnf downgrade pcre-<VERSION_BEFORE_8.40> sudo dnf versionlock add pcre

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2017-7246?

pcre: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2017-7246 being exploited?

CVE-2017-7246 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2017-7246 affect?

CVE-2017-7246 affects pcre. Severity is high (CVSS 7.8). Stack-based buffer overflow in the pcre32_copy_substring function in pcre_get.c in libpcre1 in PCRE 8.40 allows remote attackers to cause a denial of service (WRITE of size 268) or possibly have unspecified other impact via a crafted file.

How urgent is CVE-2017-7246?

Priority 49/100. High severity

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CVE-2017-7245 HIGH 7.8 DOWNGRADE Stack-based buffer overflow in the pcre32_copy_substring function in pcre_get.c in libpcre1 in PCRE 8.40 allow
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CVE-2017-7186 HIGH 7.5 DOWNGRADE DOWNGRADE libpcre1 in PCRE 8.40 and libpcre2 in PCRE2 10.23 allow remote attackers to cause a denial of service (segment

References

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