Malicious PDF — malware analysis report

Static analysis result for SHA-256 f28940a793a2ebe9…

MALICIOUS

PDF

85.1 KB Created: 2021-07-19 00:36:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 96527b814ebcd49e0f8163218f9d1adc SHA-1: 5d05fdca657d7787746cc988de06574381910596 SHA-256: f28940a793a2ebe9e91e91d0462ea568ca0c9d76b57ba7447e2bf97f4fd68739
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites hosted on compromised WordPress installations, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document's structure as a link farm, with many distinct hosts and disposable hosting patterns, further supports its use in a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://f27szerviz.hu/upload/files/53190963261.pdf
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac013d6346---19254315649.pdf
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609d65d35dd29---18602910148.pdf
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075db7aca979---desejonokufodimatopi.pdf
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/2tredmu7mq3p4j5krse02lmu7q/38009712758.pdf
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/7143b68c1f0ae97bc6a5c46900117107/tevojepuramixenup.pdf
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/af02b88b041d223cfbe46da507da9955/84297223333.pdf
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/25126a14e88dcaaf32c5329ec43becae/vukesevusure.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081dab520f77---5556795827.pdf
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/160aab7e1bf26d---69440787616.pdf
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/27346273315.pdf
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078514ad9b44---54101139933.pdf
    • http://faxik.online/ckfinder/userfiles/files/95166286908.pdf
    • http://mdknoodles.co/uploads/files/59014967065.pdf
    • http://uamarkets.com/images/file/kiremexe.pdf
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606e87a91d321---16292018493.pdf
    • http://namuvaldymas.lt/userfiles/file/91800003766.pdf
    • http://abakus-routing.co.uk/ckfinder/userfiles/files/42522568424.pdf
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/a87a5d33cc89de3c2f13e944c04cd873/68818230314.pdf
    • http://www.jobsincrete.gr/images/_user_na/file/jijom.pdf
    • http://accessiblevehicleservices.com/userfiles/file/fogotuxi.pdf
    • https://zohopinler.com/calisma2/files/uploads/losetiralaboraloj.pdf
    • http://15thstpresbyterian.org/clients/d/d7/d7025cfb1d4df99eee5a588ecc3dd57f/File/27277043527.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bd9d91e4862---94773615331.pdf
    • https://accu-split.com/userfiles/files/65884927174.pdf
    • http://alemotta.com/resources/original/file/89268776146.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+copy+and+paste+pdf+files+into+word
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/cbb0df20b006381b87a753030113f6ba/gagokimezemelowosukagog.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_off0000e8a3.bin
eb96ab5c505c768abcfd5c9045519d6ffb10acab9fe3733d160592adbe67acf6
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8A3 17132 bytes
font_01_sfnt_off00011562.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11562 16792 bytes
font_02_sfnt_off00012d79.bin
f9c20be42fc07daeda6c5d89ea993361546741c3c1db7af930c54325fcd2404d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D79 10804 bytes