Malicious PDF — malware analysis report

Static analysis result for SHA-256 36c8e2772f31f1fd…

MALICIOUS

PDF

77.1 KB Created: 2021-09-03 22:44:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ae03c806f678b31ab644ee29a9fc38f8 SHA-1: b6600f58b5df7f9cca3789a50027ba7fb733116c SHA-256: 36c8e2772f31f1fdd844b69004ff1ef33038af0c4d8b5c8c6505f8d9642bfb42
256 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The PDF contains multiple heuristics indicating it is a lure for sensitive information, specifically a 'Recovery secret / private key request' and a 'Password-protected archive handoff'. The presence of numerous external URLs, many pointing to compromised WordPress sites, suggests an attempt to host malicious content or redirect users to phishing pages. ClamAV also detected this file as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 8

  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://crysiq.ru/uplcv?utm_term=pdf+encryption+pdf
    • https://gujaratisamajparis.org/upload/files/83288304831.pdf
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16118de7da9d77---piludimuxudutisaposavuwol.pdf
    • http://businesslegalgroup.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/ximutotufogejumukoxofuvo.pdf
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/580183a44a16896ffba359df19e017a1/52945850258.pdf
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160825a4820785---87541033840.pdf
    • http://anandtouristcorporation.com/uploads/89858746920.pdf
    • https://thaiwoodengames.com/files/upload/files/35812465603.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1609fcd4c7403e---kowowevuwivinovem.pdf
    • http://iehyun.com/editorupload/file/9027733502.pdf
    • http://jingyitech.com/uploadfile/40576715140.pdf
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/vulus.pdf
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d8536bc08b6---datixuwusaxufamugagixata.pdf
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/a878d81e16243f9f06285ac8a73d78a9/vosok.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/62t3rord84jj39v6ao9rbn816q/28398882405.pdf
    • https://lompatjauh.com/contents/files/39124451519.pdf
    • http://staresecurity.com/userfiles/file/21828538445.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cb41.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB41 16792 bytes
font_01_sfnt_off0000e358.bin
7db7c6052b4cd2625dc32ba5dadd5e56f7d30021f1f780a18f2fecacca9441dd
pdf-font-stream PDF embedded font (sfnt) at offset 0xE358 10352 bytes
font_02_sfnt_off0000facf.bin
d53a809eca03f9dbf25a508681651ce01528b70d6538bcb9c4f621e1e8cc925f
pdf-font-stream PDF embedded font (sfnt) at offset 0xFACF 17276 bytes