The XXE half carries a precondition the advisory states plainly: log4net has to parse a configuration file the attacker controls [3]. That is a promotion of access someone already has, not a way in. Whoever can write into the ASE2000 installation directory converts that write into arbitrary local file reads and outbound requests from the host [4], which is why the first interim measure is a permissions change on the install directory and its config files rather than anything on the network [8].
CVE-2026-18717 is the one that works from the wire. In versions 2.35 through 2.37 the IEC 60870-5-104 TLS client does not validate certificate error conditions correctly, so an attacker positioned to intercept can present a certificate, complete the handshake as the trusted peer, and read or modify what crosses the session [5][6]. A test set that accepts a forged peer is describing the attacker's traffic to the engineer reading its output, and on a commissioning link there is usually no second source to compare against.
The two bugs do not cover the same ground. Counting the listed range, 2.25 through 2.37 is 13 releases [10]; the certificate flaw is scoped to three of them [11], leaving ten builds exposed only to the log4net issue [12]. Both close on the same version, so the split does not buy anyone a smaller upgrade: every customer between 2.25 and 2.37 is told to move to 2.38 or later [7].
Upstream log4net fixed the entity handling in 2.0.10 [3]. Version 2.38 ships 3.3.1.0, well past the minimum that would have closed it [14]. The identifier attached to that flaw is CVE-2018-1285, eight years older than the certificate CVE published alongside it [13]. That gap is the interesting number here: the fix had been available upstream the whole time, and the clock was running on the vendor rebuild.
The advisory as supplied lists no CVSS metrics and no report of exploitation in the wild [9]. So this sits in the inventory column. The questions worth answering are which hosts run 2.35 or later, who has write access to their program directories, and whether the IEC 104 TLS sessions those hosts open cross a network the operator does not own [8].
