Malicious PDF — malware analysis report

Static analysis result for SHA-256 5af00fdfb26e5b76…

MALICIOUS

PDF

86.7 KB Created: 2021-08-01 14:51:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5297fac58edc1e8c03b63d3e20e5e089 SHA-1: 99646803bc30e66876e3cc5065e2d98a2190b165 SHA-256: 5af00fdfb26e5b763baf7eca4a7ca79a65b8bb46a9da05a585e5ed6f8cdb7768
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a phishing or malware distribution lure. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the presence of external links and the nature of the heuristics point towards a common pattern of using malicious documents to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://klimatyzacjaradom.pl/userfiles/file/32022397543.pdf
    • http://arci-mp.fr/admin/File/67849530001.pdf
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/i1ig79gifv56pulh0694st8o55/38819337084.pdf
    • https://ancoraeducacion.com/images/dirotomak.pdf
    • http://ardechetendancebrut.fr/userfiles/ardechetendancebrut.fr/file/bipepimuvaxojugesedipeluw.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/8rl0iqf50ks3h2vlms3j36san6/tadaxof.pdf
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fdedc7c1ac---73353317853.pdf
    • http://gitishahjahanpur.org/ckfinder/userfiles/files/zurupifimapikeleko.pdf
    • http://hagelkonzept.com/userfiles/file/56473926951.pdf
    • http://dalnoboy.org/data/filestorage/upload/files/51945409678.pdf
    • http://geluidsadviesnederland.nl/ckfinder/userfiles/files/dakuv.pdf
    • http://gildiamasterov.ru/userfiles/file/vujasotasijexopajon.pdf
    • http://portalcom-b2b.es/img/user///file/_0426115001623636293.pdf
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/2cd2b6b1091f12eaf132724ecbdf3667/dapafuretekujib.pdf
    • https://giridhareye.org/ckfinder/userfiles/files/tazofejetunek.pdf
    • https://ezgoe.com/10005001208290177/ckfinder/userfiles/files/kuxigugotopegenevibi.pdf
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/6c7df4e1ddb3f0bc17659b1e4154263b/tegimebupasisinapetafejez.pdf
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160707a7a70ad0---1731436395.pdf
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/16080c15d0d054---kunanimifef.pdf
    • https://peilimineko.com/userfiles/file/2821944995.pdf
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab6b499f81b---marefinu.pdf
    • http://www.contectrade.hu/fckfiles/file/kemotanuxaxixi.pdf
    • http://aarogyamedico.com/userfiles/file/temusedojaleva.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/4e45196e8b1514f8c4477f502a94bd23/54917574770.pdf
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160753c0c0e1c1---julizexevivekubamajukama.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=passe+compose+et+imparfait+exercices+fle
    • 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_off0000e8b2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B2 16792 bytes
font_01_sfnt_off000100c4.bin
8fc9b7d3217329edfaea648437d82dd3d39652a49c611e377ee016ec9b49d0a3
pdf-font-stream PDF embedded font (sfnt) at offset 0x100C4 19560 bytes
font_02_sfnt_off00013214.bin
ced1b35a4498df76e0ed5b8211f5818b8f64963420f45acac3e6a032b55f2710
pdf-font-stream PDF embedded font (sfnt) at offset 0x13214 10640 bytes