ALAS2ECS-2026-148

References: CVE-2026-17106  CVE-2026-56855  CVE-2026-61801  CVE-2026-78662  CVE-2026-78667  CVE-2026-81870  CVE-2026-92542  CVE-2026-92543  CVE-2026-93320 
FAQs regarding Amazon Linux ALAS/CVE Severity

Issue Overview:

The tar extraction routines in moby/go-archive (Unpack, UnpackLayer, Untar/UntarUncompressed, and the ApplyLayer helpers) do not confine filesystem operations to the destination directory. A crafted archive can create or overwrite files outside the intended destination. (CVE-2026-17106)

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking. (CVE-2026-56855)

The `github.com/moby/sys/user` package provides Go utilities for parsing and looking up entries in Unix-style user and group database files. Versions before 0.4.1 do not sufficiently limit entries when parsing `/etc/passwd`- or `/etc/group`-style files, allowing an attacker who can supply a specially crafted file to cause excessive memory consumption and potentially terminate the affected process due to an out-of-memory condition. This issue is patched in version 0.4.1. As a workaround, avoid parsing attacker-controlled user or group database files, or validate and limit untrusted input before parsing it. (CVE-2026-61801)

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection. Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection. (CVE-2026-78662)

When parsing a Range header containing a large number of small ranges, FileServer(FS), ServeContent, and ServeFile(FS) could consume an excessive amount of CPU.

These functions now ignore Range headers containing more than 200 ranges.
The limit is controlled by the new httpservecontentmaxranges=GODEBUG setting. Setting GODEBUG=httpservecontentmaxranges=0 disables the limit.

NOTE: https://www.openwall.com/lists/oss-security/2026/10/08/9
NOTE: https://github.com/golang/go/issues/81858
NOTE: Fixed by: https://github.com/golang/go/commit/ababc3cd873d8acce1777268aa7a817e6b672028 (go1.27.2)
NOTE: Fixed by: https://github.com/golang/go/commit/eb25b4e532c5a01f99ef860ec66743a8783f992b (go1.26.9) (CVE-2026-78667)

OpenTelemetry-Go is the Go implementation of OpenTelemetry. From version 1.5.0 to 1.44.0, sdk/trace.NewTracerProvider emits a TracerProvider created internal Info-level diagnostic event whose MarshalLog implementations recursively include span processor, exporter, and client configuration. Applications that call otel.SetLogger to enable OpenTelemetry internal Info logging can therefore record OTLP gRPC and HTTP collector endpoints, the OTLP HTTP Insecure flag, and complete Zipkin collector URLs. A person or system with access to those logs can learn internal collector topology and can recover credentials or tokens embedded in Zipkin URL user information or query strings. The default OpenTelemetry logger does not emit the event, and this path does not log OTLP authentication headers, TLS key material, or span payloads. This issue is fixed in version 1.45.0. (CVE-2026-81870)

The firewall rules which mark VXLAN datagrams for encryption indiscriminately match both authentic VXLAN datagrams sent from the kernel and forged datagrams sent by user processes. Any packet sent from the host network namespace of a Linux Swarm node is encrypted with the overlay-network IPsec parameters which meets the following criteria:

- UDP datagram
- Destination port is the Swarm data-path port
- Datagram starts with a VXLAN header for the VNI of an encrypted overlay network which any running container on the node is connected to (CVE-2026-92542)

Docker Engine classifies a registry hostname as insecure using an any-match DNS check. loadInsecureRegistries() injects 127.0.0.0/8 and ::1/128 as insecure CIDRs by default. isCIDRMatch resolves all of the hostname's addresses and returns true if a single address is in the insecure CIDR list. Because the transport re-dials the hostname rather than the CIDR-matching address, a DNS answer set of one loopback IP plus a non-loopback attacker IP disables certificate verification and enables HTTP fallback for the registry connection. (CVE-2026-92543)

BuildKit may be tricked into performing file actions with special file inodes where regular files are expected. Special files may block operations or, on rootful workers, allow unintended host device access. (CVE-2026-93320)

Issue Correction:
Run yum update docker or yum update --advisory ALAS2ECS-2026-148 to update your system.

New Packages:

aarch64:
    docker-25.0.18-1.amzn2.0.1.aarch64
    docker-debuginfo-25.0.18-1.amzn2.0.1.aarch64

src:
    docker-25.0.18-1.amzn2.0.1.src

x86_64:
    docker-25.0.18-1.amzn2.0.1.x86_64
    docker-debuginfo-25.0.18-1.amzn2.0.1.x86_64

Changelog:

2026-11-02: CVE-2026-61801 was added to this advisory.

2026-11-02: CVE-2026-81870 was added to this advisory.

2026-11-02: CVE-2026-56855 was added to this advisory.

2026-11-02: CVE-2026-78662 was added to this advisory.