CVE-2019-6978

CVE-2019-6978 is a critical-severity vulnerability in Libgd with a CVSS 3.x base score of 9.8. 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-415.

Key facts

• Severity: Critical (CVSS 3.x base score 9.8)
• CVSS v2: 7.5
• EPSS exploit prediction: 4% (90th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-415
• Affected product: Libgd
• Published: 2019-01-28
• Last modified: 2026-06-17

Description

The GD Graphics Library (aka LibGD) 2.2.5 has a double free in the gdImage*Ptr() functions in gd_gif_out.c, gd_jpeg.c, and gd_wbmp.c. NOTE: PHP is unaffected.

Frequently asked questions

What is CVE-2019-6978?

The GD Graphics Library (aka LibGD) 2.2.5 has a double free in the gdImage*Ptr() functions in gd_gif_out.c, gd_jpeg.c, and gd_wbmp.c. NOTE: PHP is unaffected.

How severe is CVE-2019-6978?

CVE-2019-6978 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-6978 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-6978?

CVE-2019-6978 primarily affects Libgd. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-6978?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2019-6978 published?

CVE-2019-6978 was published on 2019-01-28 and last updated on 2026-06-17.

References

• http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00025.html
• http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00031.html
• https://access.redhat.com/errata/RHSA-2019:2722
• https://github.com/libgd/libgd/commit/553702980ae89c83f2d6e254d62cf82e204956d0
• https://github.com/libgd/libgd/issues/492
• https://github.com/php/php-src/commit/089f7c0bc28d399b0420aa6ef058e4c1c120b2ae
• https://lists.debian.org/debian-lts-announce/2019/01/msg00028.html
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3CZ2QADQTKRHTGB2AHD7J4QQNDLBEMM6/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3WRUPZVT2MWFUEMVGTRAGDOBHLNMGK5R/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEYUUOW75YD3DENIPYMO263E6NL2NFHI/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TTXSLRZI5BCQT3H5KALG3DHUWUMNPDX2/
• https://security.gentoo.org/glsa/201903-18
• https://usn.ubuntu.com/3900-1/
• https://www.debian.org/security/2019/dsa-4384

Affected products (7)

• cpe:2.3:a:libgd:libgd:2.2.5:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*

More vulnerabilities in Libgd

• CVE-2016-10166 — Critical (CVSS 9.8): Integer underflow in the _gdContributionsAlloc function in gd_interpolation.c in the GD Graphics Library (aka libgd)…
• CVE-2016-6912 — Critical (CVSS 9.8): Double free vulnerability in the gdImageWebPtr function in the GD Graphics Library (aka libgd) before 2.2.4 allows…
• CVE-2016-8670 — Critical (CVSS 9.8): Integer signedness error in the dynamicGetbuf function in gd_io_dp.c in the GD Graphics Library (aka libgd) through…
• CVE-2016-7568 — Critical (CVSS 9.8): Integer overflow in the gdImageWebpCtx function in gd_webp.c in the GD Graphics Library (aka libgd) through 2.2.3, as…
• CVE-2016-3074 — Critical (CVSS 9.8): Integer signedness error in GD Graphics Library 2.1.1 (aka libgd or libgd2) allows remote attackers to cause a denial…
• CVE-2016-5116 — Critical (CVSS 9.1): gd_xbm.c in the GD Graphics Library (aka libgd) before 2.2.0, as used in certain custom PHP 5.5.x configurations,…

All CVEs affecting Libgd →

Other CWE-415 (Double Free) vulnerabilities

• CVE-2018-0101 — Critical (CVSS 10.0): A vulnerability in the Secure Sockets Layer (SSL) VPN functionality of the Cisco Adaptive Security Appliance (ASA)…
• CVE-2026-8925 — Critical (CVSS 9.8): The curl logic that works with SASL authentication could end up cleaning up the GSASL context *twice* without clearing…
• CVE-2020-37239 — Critical (CVSS 9.8): libbabl 0.1.62 contains a broken double free detection vulnerability that allows attackers to bypass memory safety…
• CVE-2026-43011 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: net/x25: Fix potential double free of skb When…
• CVE-2026-31609 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: smb: client: avoid double-free in…
• CVE-2026-31608 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: smb: server: avoid double-free in…

Browse all CWE-415 (Double Free) vulnerabilities →