Vulnerabilities

CVE-2026-59090 is an unsigned integer underflow (CWE-191) in the block_rem variable of GIMP's PSD file-format plugin. It is triggered when a user opens a specially crafted .psd image file, causing the parser to lose track of block boundaries and allowing an attacker to inject arbitrary data as layer resource blocks. Successful exploitation can ultimately result in arbitrary code execution on the victim's system. Any system running a vulnerable GIMP build, including the GIMP package shipped with Red Hat Enterprise Linux, is affected if it is used to open untrusted PSD files; the source data does not specify affected or fixed version ranges. No in-the-wild exploitation is reported (not in CISA KEV, EPSS ~0.6%), but a public proof-of-concept reference exists via the GNOME GitLab issue tracker (issue #16509).

Do: Inventory endpoints for GIMP installations, prioritizing users who receive third-party PSD files, and upgrade to a patched GIMP build once Red Hat or GNOME publish fixed versions (no fixed version is given in this data; track GNOME GitLab issue #16509 and Red Hat security advisories). Until patched, treat unsolicited or untrusted .psd files as untrusted input and open them only in a sandboxed environment or with an alternative viewer. Note the reported EPSS probability (0.6%) is low and there is no KEV listing, so this is a hardening priority rather than an active-incident response.

Libkcapi, the user-space library that exposes the Linux kernel crypto API, improperly reuses the same initialization vector (IV) for every internal 64 KiB data chunk when a one-shot symmetric cipher operation is performed on inputs larger than 64 KiB in stateful modes such as Counter (CTR) or Cipher Block Chaining (CBC). A remote attacker can trigger the flaw by causing an application that uses libkcapi to process specially crafted large inputs. Repeated IV use in these modes exposes relationships in the encrypted plaintext, so the attacker gains degraded confidentiality of the processed data and possibly incorrect cryptographic processing affecting integrity, though not code execution. Affected parties are users of the upstream smuellerdd libkcapi project and Red Hat distributions and images that ship it (Red Hat Enterprise Linux, Red Hat hardened images, and OpenShift Container Platform), limited to deployments where applications actually link and call the library. No exploitation in the wild is known; the issue is documented in a public Red Hat Bugzilla reference, and EPSS currently assigns a 0.3% probability of exploitation in the next 30 days.

Do: Upgrade libkcapi to the fixed release published by the upstream project or via Red Hat advisories covering Red Hat Enterprise Linux, hardened images, and OpenShift, and track Red Hat Bugzilla #2462011 (https://bugzilla.redhat.com/show_bug.cgi?id=2462011) for fix details. As an interim mitigation, have applications avoid one-shot symmetric operations on inputs larger than 64 KiB in CTR or CBC, instead processing data in smaller chunks with freshly initialized IVs. Inventory which deployed systems and applications link against libkcapi to confirm actual exposure, since the flaw only matters for code paths that call the library.

An integer overflow (CWE-190) in the file-fits plugin bundled with GIMP causes image width and height values from a FITS file to be multiplied using signed 32-bit arithmetic; when a crafted file sets both dimensions large enough that the product exceeds 2^31, the plugin allocates an undersized heap buffer, and cfitsio's subsequent write of a full pixel row overflows it. The flaw is triggered when a user opens or processes a maliciously crafted FITS image in GIMP, consistent with the CVSS local attack vector requiring user interaction (AV:L/UI:R). Successful exploitation corrupts heap memory and can potentially lead to arbitrary code execution with the victim user's privileges, or crash the application in a denial of service. Anyone running GIMP with the FITS loader enabled is affected, including GIMP packages shipped with Red Hat Enterprise Linux. There are no reports of in-the-wild exploitation (not in CISA KEV; EPSS 0.3%), but a public issue with a proof-of-concept reference exists on the GNOME GitLab tracker.

Do: Update GIMP via your distribution's package channel once a patched release is available and watch for a Red Hat security advisory covering Enterprise Linux (fixed version numbers are not given in the source data). As an interim mitigation, avoid opening untrusted .fits files in GIMP and check whether the file-fits plugin is enabled in your build. Public PoC details are tracked in GNOME GitLab issue 16528.

A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.

A heap out-of-bounds read flaw was found in libsoup. When parsing multipart HTTP messages, an integer type mismatch between the caller and soup_headers_parse() can cause the length parameter to be incorrectly truncated, leading to a heap buffer over-read. A remote attacker could use this flaw to crash an application using libsoup or potentially disclose heap memory contents.

A flaw was found in GIMP's PSD parser. An integer overflow in read_RLE_channel() can cause an undersized heap allocation for the RLE row-length table, after which subsequent per-row writes corrupt heap memory. This could lead to memory corruption, potentially resulting in denial of service or arbitrary code execution.

A flaw was found in GIMP's PNM file format parser. When parsing a specially crafted PNM file, the pnmscanner_gettoken() function writes a null terminator one byte past the end of a stack-allocated buffer due to an off-by-one error in the loop boundary check. This could lead to memory corruption, potentially resulting in denial of service or arbitrary code execution.

A flaw was found in GLib. A state confusion issue exists in g_dbus_node_info_new_for_xml() in the gio/gdbusintrospection.c file when processing malformed D-Bus introspection XML, specifically with a `node` element nested within other elements like `method`, `signal`, `property` or `arg`. This issue can cause an unsigned integer overflow and lead to an out-of-bounds read, resulting in a denial of service.

A flaw was found in Keycloak. A highly privileged user with `manage-clients` permission can exploit this vulnerability by injecting a hardcoded role mapper into any client. This action allows the user to bypass existing scope restrictions and inject the `realm-admin` role into generated tokens, resulting in privilege escalation and full administrative access to the realm.

A flaw was found in OpenSSH. A malicious SSH server can exploit a double free vulnerability in the Diffie-Hellman Group Exchange (DH-GEX) client path. This occurs during FIPS (Federal Information Processing Standards) mode known-group validation when the client processes attacker-controlled DH-GEX group parameters. Successful exploitation leads to client-side process termination, resulting in a Denial of Service (DoS).

The fix for CVE-2026-2443 was regressed by a subsequent rework commit that replaced specific overflow checks with a general signed comparison. When a client sends a Range request with a suffix length exceeding the content size, the resulting negative start value is not properly clamped, leading to malformed HTTP 206 responses and log flooding.

Kludex Starlette prior to version 1.0.1 did not validate the HTTP Host request header before using it to reconstruct request.url, an inconsistency classified as HTTP request/response smuggling (CWE-444). Because routing operates on the raw ASGI scope path while request.url is rebuilt from the unvalidated Host header, an attacker can send a malformed Host header so that request.url.path differs from the path the router actually processed. Any middleware or endpoint that enforces security restrictions based on request.url rather than the raw scope path can then be tricked into approving requests that should have been blocked, bypassing those controls. All Starlette deployments below 1.0.1 are affected, both direct users and downstream products that bundle the library, including Red Hat offerings such as Ansible Automation Platform, OpenShift AI, OpenShift Lightspeed, Satellite, AI Inference Server, Migration Toolkit for Applications, and Enterprise Linux AI. CISA added the flaw to the Known Exploited Vulnerabilities catalog on 2026-09-02, confirming active exploitation; related reporting describes attackers deploying reverse shells and crypto miners, and EPSS ranks it in the 98th percentile with a 36.3% probability of exploitation within 30 days.

Do: Upgrade Starlette to 1.0.1 or later, which validates the Host header against RFC 9112/RFC 3986 grammar and falls back to scope['server'] for malformed values, and apply the corresponding Red Hat updates for each bundled product listed above. Until patched, review middleware and endpoints that enforce security decisions from request.url and validate or pin the Host header at your reverse proxy or load balancer. As a KEV entry, federal agencies must patch per BOD 26-04 timelines based on each asset's internet exposure, and operators of internet-facing AI infrastructure should verify their Starlette/FastAPI dependency versions.