Malicious PDF — malware analysis report

Static analysis result for SHA-256 f89123f6105130db…

MALICIOUS

PDF

82.6 KB Created: 2021-08-27 12:33:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2396628595c9f728d69da0b3f7b62daf SHA-1: e17cd1b644ba04d1b39024e04efc31e985f9a61a SHA-256: f89123f6105130db5c088e5cbb8918ee9bd44247d6e47d72916a4a25fac90b0b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. Heuristics indicate these are likely used for phishing or to distribute further malware. The ML classifier and ClamAV detection strongly suggest malicious intent, with the primary attack pattern involving luring users through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8facbed94b---bosidovuxafadog.pdf
    • https://bookatowncar.com/userfiles/file/64156481869.pdf
    • http://www.siscbolivia.com/admin/uploaded/fck/file/lugigekofimezufu.pdf
    • http://nontaromclinic.com/ckfinder/userfiles/files/jigokuwazu.pdf
    • https://proektasis.gr/admin/spaw2/uploads/files/76456862115.pdf
    • http://fmi.lu/userfiles/files/34144533684.pdf
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/231e17121d3c112f265d20aabd90ed80/davutevav.pdf
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607319758ba0b---vuvik.pdf
    • https://xn--b8qxb801j.tw/upload/files/36530080741.pdf
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/9b35f58f5af4563c028f850aca8bd7f9/88125318231.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/efl06g5d7554j37fg3b292939j/roboxibuzosaduzexisetinot.pdf
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/23b15f13edce4a85596302b2c63db042/pubenokurot.pdf
    • https://www.ebenisterie-burette.com/ckfinder/userfiles/files/zopofuvosojezaze.pdf
    • https://realschoolspirit.net/scauserfiles/files/kurojenidilaxojalujur.pdf
    • http://drkoopman.nl/cmsimages/file/zirepepo.pdf
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/79e2d78e3551669d2a662cd4b47d9ef7/filog.pdf
    • https://hoangnhataudio.vn/media/files/89777237510.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d4b1ccaf078---xoxenajezatovakik.pdf
    • https://fullhousetourism.com/UploadFiles/file/20210516085828113.pdf
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/4d0e835aaf6d6359f3b5c76e99b206bf/18738727859.pdf
    • https://wfca-czech.cz/temp/userfiles/files/daneg.pdf
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/160c076b05684f---37848881320.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=pick+out+from
    • 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_off0000e24d.bin
c5e613e098a9ee63a80b54f8b130dc72dc04e3c4f84aada60d1c7b73e5fbcb24
pdf-font-stream PDF embedded font (sfnt) at offset 0xE24D 10080 bytes
font_01_sfnt_off0000f8cb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8CB 16792 bytes
font_02_sfnt_off000110dd.bin
34f78d225276427ecde9a235710aa5abbc11e844727af7efd3d70bc97f487f9c
pdf-font-stream PDF embedded font (sfnt) at offset 0x110DD 16540 bytes