Malicious PDF — malware analysis report

Static analysis result for SHA-256 84c16d8b37994b94…

MALICIOUS

PDF

87.4 KB Created: 2021-06-28 15:29:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 10cdefdae351d5a17dc5035feceefafe SHA-1: 6b4042aa6c2bcbf161a687846d74138094f2bde4 SHA-256: 84c16d8b37994b94115aefeacb6406d9d54f7691bf7e04b4098b53d02ce81450
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites, likely intended to redirect users to malicious content or facilitate further infection. No scripts were extracted, but the PDF structure itself is used to host these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://krisoc.ru/uplcv?utm_term=diablo+2+single+player+character+files
    • https://behbehaniprojects.com/uploads/files/tebovisi.pdf
    • https://www.spreefahrten-berlin.de/wp-content/plugins/super-forms/uploads/php/files/1doki6qm2bndjja7r7f7d7lmck/10580076493.pdf
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/b3c4c18cb20d811a591d2ae0f8457f24/mujakanifare.pdf
    • http://www.dismaplant.com/ckfinder/userfiles/files/54084168849.pdf
    • https://ltgtrends.com/wp-content/plugins/super-forms/uploads/php/files/79800e7ec5c24e54112849570353fbca/xifis.pdf
    • http://brandnewgoods.net/userfiles/file/natubanokibusop.pdf
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/37c8196c0abd44bd3eedaa8af6eea071/69709407190.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/16083dbf333d02---94755788182.pdf
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/7cd95b5cf747440d4bfccb54ca9c59e4/dejozuluraguzaxeguja.pdf
    • http://jongauger.com/ckfinder/userfiles/files/xudakexipejoparesuvafoje.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/ovd2vbhp9ubl5apqor6osejnk3/jafovuderilenaxebagarof.pdf
    • http://wsm.hk/images/uploadfiles/file/mevaxizikuposubuwulevaki.pdf
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16084feac32116---wasur.pdf
    • http://ahs1968.com/clients/d/dc/dcea35c349c70fb55dca458fc6558ff6/File/92856261733.pdf
    • https://acornschoolcharleston.org/wp-content/plugins/super-forms/uploads/php/files/3839bd8b7b9a54c29ce269813465c2cb/bomes.pdf
    • https://bobecoingatlan.com/uploads/editor/file/murufapibosedomixoruv.pdf
    • https://mk-sito.it/uploads/file/87326173767.pdf
    • http://kadh.kr/bobod/upload/file/wideb.pdf
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/e2fdb3018766a4bf397fe88651c59d7c/79075641092.pdf
    • http://kinel-hunter.ru/upfiles/file/73501339714.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c8991bd2d64---vajixiv.pdf
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/976b0ecbe2220b369827ade5283dae5a/56636365704.pdf
    • http://strandedtattoo.net/file/wiwojonovofek.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_off0000f0aa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0AA 16792 bytes
font_01_sfnt_off000108c1.bin
fbd444bc8c44d2be0d2319f9d51e5b13f45c92bb2b2821e504221989fef50bf0
pdf-font-stream PDF embedded font (sfnt) at offset 0x108C1 11136 bytes
font_02_sfnt_off00012293.bin
64628530de79679ec0a87209b52e22a9e2b62099dbc7a12a060738b12c769f44
pdf-font-stream PDF embedded font (sfnt) at offset 0x12293 17600 bytes