Malicious PDF — malware analysis report

Static analysis result for SHA-256 b41aa2f84cb41f10…

MALICIOUS

PDF

85.7 KB Created: 2021-07-01 00:20:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 33e7aa099ec149b01495527b4eba33de SHA-1: b4f752fed9430e3065c2d299c12ceff001c4a874 SHA-256: b41aa2f84cb41f1096884fa865092c708175c6c6568b96e5b2beef8da00e2fd1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous distinct hosts, many of which appear to be compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. No scripts were extracted, but the structure and URL analysis suggest a phishing or credential harvesting lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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 http://wsm.hk/images/uploadfiles/file/venawikuf.pdf
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/160873815e6c2d---jabafuvanoreziwidawizu.pdf
    • http://accessprecision.com/userfiles/file/70601613756.pdf
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/44f21dc41d3f6244c0788c04a91333d8/9383856681.pdf
    • http://ferrocom-spb.ru/userfiles/files/76355140555.pdf
    • https://wavesmaroochydore.com/wp-content/plugins/super-forms/uploads/php/files/kk10q729qdj22s994m00u6j7ph/84476139270.pdf
    • http://surtek.biz/image/files/20150115_055016.pdf
    • http://nowyhotelik.pl/userfiles/file/bonafi.pdf
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/2h7mhgvsjqvrhvcs67t6ukv8r4/83045269581.pdf
    • https://www.kasekimi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607911a4abfbf---59062536083.pdf
    • http://mahkotacare.com/tmr/userfiles/files/duxexudufosofaj.pdf
    • http://cathyknightwaite.com/ckfinder/userfiles/files/60710500285.pdf
    • https://dewalt-naradi.cz/media/upload/editor/file/xubulugerefuxuxuxetizava.pdf
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/37720353442.pdf
    • https://capitaleny.com/wp-content/plugins/super-forms/uploads/php/files/2a67eec861c68c70c4ea514af7337d0f/siwetuwiju.pdf
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608391cc87454---xekewuzejer.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/v78utriv2i53ktf4auh4tsmtf0/22839588630.pdf
    • https://portugaliaimagyarok.com/ckfinder/userfiles/files/90959136990.pdf
    • http://brilsports.ro/userfiles/file///jinubijupexixaguzinenesu.pdf
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d255f1ca6e---buzafonijepipiwaxilavu.pdf
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16091c971b19c0---12361689411.pdf
    • http://nakajima-ya.com/upload/save_image/files/17195874507.pdf
    • http://didocrosby.com/imagenes/file/59783701708.pdf
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf07f68a11---fodumuxanabapebapukik.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/fb47a6f8e96ff3b4c2eb3d6c5fb19712/sokiravavavedumopajil.pdf
    • http://hongshengfish.com/uploadfiles/2021052222322510410.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=catalina+croquettes+in+air+fryer
    • 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_off0000ebef.bin
0629ea7aa9ea5837380fb9582bfa23a23b19ecc8bcbb56a258d0f92e59f4276c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBEF 17128 bytes
font_01_sfnt_off00011892.bin
19ccd8860e5991136705fc898a277e0c8c26f920abaa9661780dd46b599f6b9c
pdf-font-stream PDF embedded font (sfnt) at offset 0x11892 10720 bytes
font_02_sfnt_off00013169.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13169 16792 bytes