Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ab43cb23d095ba4…

MALICIOUS

PDF

87.3 KB Created: 2021-09-19 08:35:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c7b1f8532df0b321c11df0fa533093a0 SHA-1: c1a76f6780b9f304a7907ce9bf8f7cecafa25529 SHA-256: 8ab43cb23d095ba4bcc26bd4f85618f12f6aecb054c544894e51497c8a7b059c
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 websites hosted on compromised CMS platforms or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://bjjiffy.com/upload/piraz.pdf
    • http://dsfly.com/uploads/files/765613060.pdf
    • http://neurooperations.com/ckfinder/userfiles/files/68888118557.pdf
    • https://mehregancenter.ir/images/upload/files/futikaruxosakageda.pdf
    • http://criminisiepartners.it/userfiles/files/81757945830.pdf
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/161352303aacc4---9642238408.pdf
    • http://iseveranscopy.com/upload/editor/file/59457609866.pdf
    • https://pepsima.biz/files/file/54563164674.pdf
    • http://spain-ex.com/images/blog/file/99858813211.pdf
    • http://thibidi.vinadesign.info/uploads/images/files/tusapaguzofafixo.pdf
    • https://berbagiangka.com/contents/files/81524613756.pdf
    • https://avukat.dnsaktif.net/upload/files/20640642849.pdf
    • https://securitydm.net/slicice/file/84291654428.pdf
    • https://go2germany.ru/files/file/49157221521.pdf
    • http://artecgroupservices.com/imagenes/file/83966352476.pdf
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613a2b924a76a---gagaj.pdf
    • https://tutorlookup.com/ckeditor/ckfinder/userfiles/files/luvejefujusapes.pdf
    • https://intervalhousehamilton.org/ckfinder/userfiles/files/38540019414.pdf
    • http://skncn.com/u/files/rowufofopevovupedezamaloz.pdf
    • http://safarekhoob.ir/basefile/safarekhoobir/files/64628009161.pdf
    • http://areaengineeringsrl.eu/userfiles/files/19760059075.pdf
    • http://mebelhotel.ru/images/news/file/26514729954.pdf
    • https://www.jnvhardoi.org/ckfinder/userfiles/files/32267828469.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=anarchist+cookbook+1971+pdf
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/533765eb546969b5358ec08db49bcd54/zinosorajaralopugunobu.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_off0000ed8a.bin
257ed802223f951c1f242681ae9cd68117900505b6e604c8985fcdc0fcc330d4
pdf-font-stream PDF embedded font (sfnt) at offset 0xED8A 11024 bytes
font_01_sfnt_off00010710.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10710 16792 bytes
font_02_sfnt_off00011f22.bin
7c35b6a6ccb0c0f10065dc4ad9966ad9eae494fc89a4fa2a2232bafe22bc3991
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F22 18692 bytes