Operation RoundPress focusing on high-value webmail servers

Operation RoundPress focusing on high-value webmail servers


This blogpost introduces an operation that we named RoundPress, focusing on high-value webmail servers with XSS vulnerabilities, and that we assess with medium confidence is run by the Sednit cyberespionage group. The last word objective of this operation is to steal confidential information from particular e-mail accounts.

Key factors of this blogpost:

  • In Operation RoundPress, the compromise vector is a spearphishing e-mail leveraging an XSS vulnerability to inject malicious JavaScript code into the sufferer’s webmail web page.
  • In 2023, Operation RoundPress solely focused Roundcube, however in 2024 it expanded to different webmail software program together with Horde, MDaemon, and Zimbra.
  • For MDaemon, Sednit used a zero-day XSS vulnerability. We reported the vulnerability to the builders on November 1st, 2024 and it was patched in model 24.5.1.
  • Most victims are governmental entities and protection corporations in Jap Europe, though we’ve noticed governments in Africa, Europe, and South America being focused as properly.
  • We offer an evaluation of the JavaScript payloads SpyPress.HORDE, SpyPress.MDAEMON, SpyPress.ROUNDCUBE, and SpyPress.ZIMBRA.
  • These payloads are in a position to steal webmail credentials, and exfiltrate contacts and e-mail messages from the sufferer’s mailbox.
  • Moreover, SpyPress.MDAEMON is ready to arrange a bypass for two-factor authentication.

Sednit profile

The Sednit group – often known as APT28, Fancy Bear, Forest Blizzard, or Sofacy – has been working since at the very least 2004. The US Division of Justice named the group as a kind of chargeable for the Democratic Nationwide Committee (DNC) hack simply earlier than the 2016 US elections and linked the group to the GRU. The group can be presumed to be behind the hacking of world tv community TV5Monde, the World Anti-Doping Company (WADA) e-mail leak, and lots of different incidents. Sednit has a diversified set of malware instruments in its arsenal, a number of examples of which we’ve documented beforehand in our Sednit white paper from 2016.

Hyperlinks to Sednit

On September 29th, 2023, we detected a spearphishing e-mail, a part of Operation RoundPress, despatched from katecohen1984@portugalmail[.]pt (envelope-from deal with). The e-mail exploited CVE‑2023‑43770 in Roundcube. This e-mail deal with is similar to those utilized in different Sednit campaigns in 2023, as documented by Unit42 for instance.

Leveraging a community scan we ran in February 2022, we discovered the server 45.138.87[.]250 / ceriossl[.]information, which was configured in the identical distinctive means as 77.243.181[.]238 / global-world-news[.]internet. The previous was talked about in a Qianxin blogpost describing a marketing campaign abusing CVE-2023-23397 that attributed it to Sednit. The latter is a site utilized in Operation RoundPress in 2023.

Given these two parts, we imagine with medium confidence that Operation RoundPress is carried out by Sednit.

Victimology

Desk 1 and Determine 1 element targets of Operation RoundPress in 2024, from ESET telemetry and two samples on VirusTotal.

Many of the targets are associated to the present battle in Ukraine; they’re both Ukrainian governmental entities or protection corporations in Bulgaria and Romania. Notably, a few of these protection corporations are producing Soviet-era weapons to be despatched to Ukraine.

Different targets embody African, EU, and South American governments.

Desk 1. Operation RoundPress victims in 2024

Date Nation Sector
2024-05 Greece Nationwide authorities.
Romania Unknown (VirusTotal submission).
Ukraine Specialised Prosecutor’s Workplace within the Subject of Protection of the Western Area (VirusTotal submission).
2024-06 Bulgaria Telecommunications for the protection sector.
Cameroon Nationwide authorities.
Ukraine Army.
2024-07 Ecuador Army.
Ukraine Regional authorities.
Serbia Nationwide authorities.
2024-09 Cyprus An instructional in environmental research.
Romania Protection firm.
Ukraine Army.
2024-10 Bulgaria Protection firm.
2024-11 Bulgaria Protection firm (not the identical as in 2024-10).
Ukraine Civil air transport firm.
Protection firm.
2024-12 Ukraine State firm within the transportation sector.
Figure 1. Map of Operation RoundPress victims in 2024
Determine 1. Map of operation RoundPress victims in 2024

Compromise chain

Preliminary entry

In 2023, Sednit was exploiting CVE-2020-35730, a recognized XSS vulnerability in Roundcube (see this CERT-UA blogpost and this Recorded Future report), which permits the loading of arbitrary JavaScript code within the context of the webmail window.

In 2024, we noticed totally different XSS vulnerabilities getting used to focus on further webmail software program: Horde, MDaemon, and Zimbra. Sednit additionally began to make use of a newer vulnerability in Roundcube, CVE-2023-43770. The MDaemon vulnerability (CVE-2024-11182, now patched) was a zero day, almost definitely found by Sednit, whereas those for Horde, Roundcube, and Zimbra have been already recognized and patched.

Sednit sends these XSS exploits by e-mail. The exploits result in the execution of malicious JavaScript code within the context of the webmail shopper net web page operating in a browser window. Subsequently, solely information accessible from the sufferer’s account could be learn and exfiltrated.

Notice that, to ensure that the exploit to work, the goal should be satisfied to open the e-mail message within the susceptible webmail portal. Because of this the e-mail must bypass any spam filtering and the topic line must be convincing sufficient to entice the goal into studying the e-mail message.

Determine 2 summarizes the compromise chain utilized in Operation RoundPress.

Figure 2. Operation RoundPress compromise chain
Determine 2. Operation RoundPress compromise chain

Usually, the e-mail message seems benign and accommodates textual content about information occasions. For instance, on September 11th, 2024, a Ukrainian goal obtained a phishing e-mail from kyivinfo24@ukr[.]internet with the topic СБУ схопила банкіра, який працював на ворожу воєнну розвідку в Харкові (machine translation: SBU arrested a banker who labored for enemy navy intelligence in Kharkiv). The message physique – see Determine 3 – accommodates excerpts (in Ukrainian) and hyperlinks to articles from Kyiv Publish, a widely known newspaper in Ukraine. The malicious code that triggers the XSS vulnerability is contained in the HTML code of the e-mail message’s physique and isn’t straight seen to the person.

Figure 3. Malicious email message sent by Sednit
Determine 3. Malicious e-mail message despatched by Sednit

One other instance is an e-mail from workplace@terembg[.]com to a Bulgarian goal on November 8th, 2024, with the topic Путин се стреми Тръмп да приеме руските условия вдвустранните отношения (machine translation: Putin seeks Trump’s acceptance of Russian circumstances in bilateral relations). The message physique – see Determine 4 – once more accommodates excerpts (in Bulgarian) and hyperlinks to articles from Information.bg, a respectable Bulgarian newspaper.

Figure 4. Another malicious email sent by Sednit
Determine 4. One other malicious e-mail despatched by Sednit

Notice that a few of these vulnerabilities should not of curiosity solely to this group: GreenCube (often known as UNC3707) and Winter Vivern have been exploiting them as properly.

Horde: Unknown exploit

For targets utilizing Horde webmail, we’ve seen Sednit utilizing an outdated vulnerability. We have been unable to seek out the precise vulnerability, but it surely seems to be an XSS flaw that was already mounted within the first model of Xss.php dedicated to GitHub, and in Horde Webmail 1.0, which was launched in 2007.

The meant exploit utilized by Sednit is proven in Determine 5. Putting malicious JavaScript code within the onerror attribute of an img component is a way taken straight from the XSS playbook: as a result of the src attribute is x, an undefined worth, onerror is named and the payload is base64 decoded after which evaluated utilizing window.mum or dad.eval.

Figure 5. Horde webmail exploit
Determine 5. Horde webmail exploit

In Horde Webmail model 1.0, the XSS filter removes the fashion parts and the on* attributes, comparable to onerror. Thus, we imagine that Sednit made a mistake and tried to make use of a nonworking exploit.

MDaemon: CVE-2024-11182

On November 1st, 2024, we detected an e-mail message despatched to 2 Ukrainian state-owned protection corporations and a Ukrainian civil air transport firm.

This message exploited a zero-day XSS vulnerability in MDaemon E-mail Server, within the rendering of untrusted HTML code in e-mail messages. We reported the vulnerability to the builders on November 1st, 2024 and it was patched in model 24.5.1, which was launched on November 14th, 2024; we then issued CVE-2024-11182 for it.

The exploit utilized by Sednit is proven in Determine 6. Simply as for Horde, it depends on a specifically crafted img component, however makes use of a bug within the MDaemon HTML parser the place a noembed finish tag inserted throughout the title attribute of a p component methods the parser into rendering the instantly succeeding img tag.

Figure 6. Exploit for CVE-2024-11182 in MDaemon
Determine 6. Exploit for CVE-2024-11182 in MDaemon

Roundcube: CVE-2023-43770

For targets utilizing Roundcube webmail: in 2023, Sednit used the XSS vulnerability CVE‑2020‑35730, whereas in 2024, it switched to CVE-2023-43770.

The newer vulnerability was patched on September 14th, 2023 in this GitHub commit. The repair is in a regex within the rcube_string_replacer.php script. The exploit utilized by Sednit is sort of easy and is depicted in Determine 7.

Figure 7. Exploit for CVE-2023-43770 in Roundcube
Determine 7. Exploit for CVE-2023-43770 in Roundcube

In rcube_string_replacer.php, URLs are transformed to hyperlinks, and the hyperlink textual content is what is predicted to be supplied between the outer set of sq. brackets. The bug lies in the truth that the hyperlink textual content is just not correctly sanitized, permitting the characters < and >. This allows an attacker to supply JavaScript code contained between