CVE-2026-53877: 
Django vulnerability analysis and mitigation

CVE-2026-53877 is a heap buffer over-read vulnerability in Django's django.contrib.gis.gdal.GDALRaster component, allowing unauthenticated network attackers to disclose adjacent heap memory or cause service degradation via segmentation fault. It affects Django 6.0 before 6.0.7 and Django 5.2 before 5.2.16; earlier unsupported series (5.0.x, 4.1.x, 3.2.x) were not evaluated but may also be affected. The vulnerability was disclosed on July 7, 2026, and was reported by Bence Nagy (Django Security Releases, GitHub Advisory). It carries a CVSS v3.1 base score of 4.8 (Medium) and a CVSS v4.0 base score of 6.3 (Medium) (GitHub Advisory).

The root cause is classified as CWE-805 (Buffer Access with Incorrect Length Value) and CWE-126 (Buffer Over-read): when django.contrib.gis.gdal.GDALRaster is instantiated from a bytes object representing a raster file, the vsi_buffer property reads approximately 32 bytes beyond the allocated in-memory buffer (Red Hat Bugzilla, GitHub Advisory). An attacker can trigger this by supplying a malformed bytes object to the GDALRaster constructor over the network, requiring no authentication or user interaction, though specific deployment conditions (attack requirements: present) must exist for the vulnerable code path to be reachable (GitHub Advisory). Patches for the 5.2.x, 6.0.x, and 6.1.x branches were prepared and are available in the Django source repository (Red Hat Bugzilla, Django Changeset).

Successful exploitation can result in partial disclosure of adjacent heap memory contents, potentially exposing sensitive data held in memory by the Django process, or cause a denial of service through a segmentation fault that crashes the application (GitHub Advisory, Red Hat Bugzilla). There is no integrity impact, and the scope is limited to the vulnerable system itself with no subsequent system impact. The vulnerability is most relevant to Django applications that use the django.contrib.gis (GeoDjango) module and accept raster data from untrusted sources (Django Security Releases).

There is no public proof-of-concept exploit and no evidence of in-the-wild exploitation at this time (GitHub Advisory). The EPSS score is approximately 0.291% (21st percentile), indicating a low near-term exploitation probability. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, and NVD's SSVC assessment classifies exploitation as "none" (GitHub Advisory).

Upgrade Django to version 6.0.7 (for the 6.0.x series) or 5.2.16 (for the 5.2.x series) to remediate this vulnerability (Django Security Releases). If immediate patching is not possible, restrict network access to application endpoints that invoke django.contrib.gis.gdal.GDALRaster with user-supplied bytes input. Users on unsupported Django series (5.0.x, 4.1.x, 3.2.x) should plan an upgrade to a supported version, as those branches were not evaluated and may also be affected (GitHub Advisory). SUSE has also released updated packages (SUSE-SU-2026:2819-1) for affected distributions (OpenSUSE Security Announce).

The Django project credited Bence Nagy for responsibly reporting the issue and published a security release announcement on July 7, 2026 (Django Security Releases). The vulnerability was discussed on the oss-security mailing list shortly after disclosure (oss-sec). Downstream Linux distributions including SUSE and Fedora have issued updated packages, and Tenable has published detection plugins for the vulnerability.