Malicious PDF — malware analysis report

Static analysis result for SHA-256 81c570fe1e5d0941…

MALICIOUS

PDF

85.3 KB Created: 2021-06-29 09:00:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cb849114883a35866cb1b793ae763d71 SHA-1: aaedfd6b106b4e7d54e7a9d7f350b491fcabd52b SHA-256: 81c570fe1e5d0941e9c5e103e163244e8f9ffa4ea64f6da1d9245f8e973d6477
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. No scripts were extracted, but the structure and URL targets are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://faresaldabbous.com/uploads/files/sevese.pdf
    • https://equinox-e.com/upload/files/57393716847.pdf
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac01ff92de7---resojajubeju.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609aa038eaf75---kananazemajaliwusewa.pdf
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609a205d45691---9315669178.pdf
    • http://vladjurnalist.ru/archive/file/befosuleriperir.pdf
    • http://ldbell1965.net/clients/85689/File/buxibebapoxazuveg.pdf
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/81dc9eefe7e3a37ada0596961219948e/pazaguzitofemififenegejal.pdf
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/g0bjtep92k9kk8a2von7m63gur/rexek.pdf
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088e3461d425---jewanepidajeg.pdf
    • http://arablift.net/userfiles/file/43012736397.pdf
    • http://dui-antidote.com/images/userfiles/file/siviviwemubagewukefovola.pdf
    • http://chokmanee.com/userfiles/file/sitig.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609875c2335ec---potuzor.pdf
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/16073aa9025604---9921789376.pdf
    • http://cablexconsulting.com/Upload/file/19495327472.pdf
    • http://nesemlak.com/test/images/uploads/files/wekuf.pdf
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/2b86cd39299339a282587d2ada84d4f3/mabevukopo.pdf
    • https://akarchlight.com/wp-content/plugins/super-forms/uploads/php/files/323b7e79af67b45ec0b1327e6d5e1156/19215361180.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a65427f3ab2---xufes.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe34ddcb44---mazim.pdf
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/2gas7oojppqpfo9ebphnob5ank/zetik.pdf
    • https://www.aserspa.net/wp-content/plugins/super-forms/uploads/php/files/fs9h03olfj17qrs1lc9kddca6a/40372311226.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=expressive+dysphasia+causes
    • 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_off0000eac3.bin
146d9cd2306cc653d9043368f3c0e057a180e70f13876b68be7b5380d4c28e74
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC3 17244 bytes
font_01_sfnt_off000117de.bin
5a52dacc414258ae5c8456f2642590217d8cbaab6c8dfb52a6095280e335137d
pdf-font-stream PDF embedded font (sfnt) at offset 0x117DE 10608 bytes
font_02_sfnt_off0001304a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1304A 16792 bytes