Malicious PDF — malware analysis report

Static analysis result for SHA-256 9008a872e4294804…

MALICIOUS

PDF

75.2 KB Created: 2021-09-24 15:59:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f0d2951efe4b0c6b22f4f4ff5e2d6462 SHA-1: b2da834c0ab942a6585acf2f0ddb4ea8ca8eb670 SHA-256: 9008a872e42948045a1d449f56fd32743e866d122a1fc6fa79b96c51221cf71e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm or redirection scheme. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but likely serving as a vessel for these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://archism.ru/uplcv?utm_term=sincronizar+google+calendar+con+calendario+android
    • http://palaciodelosnavas.com/userfiles/file/78091009496.pdf
    • https://taucaotoccatba.vn/images/news/files/60970551152.pdf
    • https://isagrinio.gr/userfiles/77867465533.pdf
    • https://www.restaurant-latableedevercel.com/ckfinder/userfiles/files/xeveman.pdf
    • http://teacherandtraining.com/coj_u/KK/userfiles/files/fudexalusomagutunugesek.pdf
    • http://avvocato-callegaro.it/public/file/57760027826.pdf
    • https://tdfstore.it/file/61816253455.pdf
    • https://almuhja.com/ckfinder/userfiles/files/78332074034.pdf
    • http://skogsformedling.se/bilder_umeny/File/12650231010.pdf
    • https://dananeye.com/uploads/files/202109081953065461.pdf
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140ef8829db9---44510864672.pdf
    • http://weforyou.it/userfiles/files/garalijaxamalovo.pdf
    • https://bbpartner.cz/userfiles/file/52377464550.pdf
    • http://www.almansori-ye.com/almansorifiles/files/46399575472.pdf
    • http://xn----8sbemnkjd7bfu.xn--p1ai/design/img/upload/file/wirem.pdf
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16145fc7a4b6aa---77107921687.pdf
    • http://ozgu-yapi.com/firma/files/jubawovojefulisosemuj.pdf
    • http://kazuma.ru/ckfinder/userfiles/files/dejezokesixerulawotawasap.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/fff566e9a0ebce4796161cd5909b6607/40510696476.pdf
    • http://tongrentangthai.com/UserFiles/file/47973226760.pdf
    • http://uniquecharacters.com/upload/files/jupovupo.pdf
    • http://dafangtour.com/fckeditor/userimages/file/mamupowujumexox.pdf
    • https://seedomoretravel.com/files/files/kaguvegojulomej.pdf
    • https://fptica.ru/images/file/wifanoxeneto.pdf
    • http://zeshengtecphar.com/UploadFiles/FCKeditor/20210913225320.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_off0000bdd4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBDD4 16792 bytes
font_01_sfnt_off0000d5e6.bin
b3656ec09a5c42cae67f454b32d0c8e6c8101604ea410d7ea2081ccd767d6de4
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E6 18840 bytes
font_02_sfnt_off00010699.bin
13c7d8c498ad551486ca52b920c075d9760fa0c1b31dc04444ba03b13d0f590c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10699 10416 bytes