Malicious PDF — malware analysis report

Static analysis result for SHA-256 42d6a6851f9a090a…

MALICIOUS

PDF

82.3 KB Created: 2021-09-03 18:25:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5536d394a27eae181183da08a2495537 SHA-1: 712290cea9764e251f94ca743319ed230d5133e2 SHA-256: 42d6a6851f9a090a4ce82de1f7252cd39da08cd9f16881babe0e0279be7dcf9a
156 Risk Score

Malware Insights

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

The PDF file contains numerous links pointing to compromised WordPress sites, suggesting it functions as a link farm to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The presence of multiple distinct hosts and the use of 'utm_term' parameters in some URLs further support the hypothesis of a coordinated distribution effort.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adb39d8dee3---84030579945.pdf
    • http://aitrans.cn/UploadFile/file/F1202108260210275866.pdf
    • http://sequoia60.com/clients/875776/File/8707830943.pdf
    • http://duszek-lasu.pl/userfiles/file/dobubuxiwafulizanubuju.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/cae00418966b312f3c34af256fb221c5/xuxuxevupezibarepozojizum.pdf
    • http://toyteepee.com/uploadfiles/file/210823180412026367jwx92n.pdf
    • https://kozhikodedeaf.org/admin/my_files/file/99710858308.pdf
    • http://accessoriesunlimitedinc.net/catalog/file/79855808101.pdf
    • http://adams-gold.ru/archive/image/file/luxikaberinelipu.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/58755e365588ee4e3e4fa367bbcb84c5/89169035375.pdf
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c0d27d7aa7e---jusasedogikow.pdf
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/cb44201dedf4bef556718bcb4a406822/34444965147.pdf
    • http://antoniolescio.net/userfiles/files/nurofodegige.pdf
    • http://botosani.ro/img/uploads/file/ledos.pdf
    • https://victorybear-info.com/userfiles/files/58494980208.pdf
    • http://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/powidubal.pdf
    • http://karmand24.ir/basefile/ehotel724ir/files/kebutexeboweligebilax.pdf
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a77359e729c---wodexuruluvetidanuzedav.pdf
    • http://allaboutdowney.com/userimages/79414313537.pdf
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1611b11525c28a---83534353820.pdf
    • https://www.pepinieres-gey.fr/ckfinder/userfiles/files/35235522262.pdf
    • http://douzonebnf.com/upload/file///67831950167.pdf
    • http://baigeleather.com/userfiles/file/71140901446.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=dot+net+interview+questions+and+answers+for+freshers+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_off0000dc72.bin
5f6a3db095f966e14acacb978e4a351ec4445d957ddb4efabfe97c99bacd0f5a
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC72 10948 bytes
font_01_sfnt_off0000f59d.bin
0464dee0dddbe735a3c3a4530a2a6f469422acd20c8398e2c3b07f3efa92ba85
pdf-font-stream PDF embedded font (sfnt) at offset 0xF59D 17452 bytes
font_02_sfnt_off000122c2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x122C2 16792 bytes