Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f428093487daf1b…

MALICIOUS

PDF

77.0 KB Created: 2021-09-20 03:33:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6ee6508d252137609d730202141233b5 SHA-1: 417554ca835baffddf7b35c2a332b38f04455ec9 SHA-256: 3f428093487daf1bb0211a329162e4c00ff8664ab45391ea82f1460c439a9895
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. Multiple URLs are embedded, some pointing to compromised CMS uploads, suggesting an attempt to lure users to external sites. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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://vln.nl/files/file/luzasumogip.pdf
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/5feccd7af45d876e63252d56141047a3/11377472373.pdf
    • http://nerezove-kuchyne.cz/UserFiles/File/gatanotisigafadobeliz.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147b6f573529---18946135222.pdf
    • https://manpowernepal.net/ckfinder/userfiles/files/pokagafuwu.pdf
    • http://stefanourso.com/public/userfiles/file/benilowixogiga.pdf
    • https://equantumconsulting.com/files/files/95747742938.pdf
    • https://webshopplus.nl/app/webroot/files/userfiles/files/76070979171.pdf
    • https://ismet.com.br/ckfinder/userfiles/files/44114414026.pdf
    • http://bjhtdszdh.com/v15/Upload/file/20219510113048.pdf
    • http://bidwoodmachine.com/d/files/88960948698.pdf
    • https://businessincasey.com.au/application/third_party/ckfinder/userfiles/files/98507224706.pdf
    • http://leaders-adv.net/userfiles/file/ligadamaxagovixelefi.pdf
    • http://onlinecommerce.bg/uploads/pages/files/noredajal.pdf
    • https://miltonmattox.com/userfiles/file/7303415035.pdf
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132f50f15a1f---20034368999.pdf
    • http://ibrahimalsada.com/pics/file/16096014016.pdf
    • http://topnotchimports.com/ckfinder/userfiles/files/70542755236.pdf
    • http://chinahongji.com/d/files/81552044458.pdf
    • http://eskuvoiiranytu.hu/blog/file/94726146636.pdf
    • http://otohyundaidanang.com/uploads/image/files/16434037583.pdf
    • http://stressmanagement-karriere.de/userfiles/file/1180506182.pdf
    • https://lingchuanfloor.com/app/webroot/userfiles/files/rowab.pdf
    • https://h16hr15k-h19hr37urn.com/contents/files/vubonederowevabijebiri.pdf
    • https://youxsoft.com/uploads/files/jasimefovapivexabifi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=best+game+on+luckyland+slots
    • 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_off0000c913.bin
e84b490647a9b6f4c0c88a03be39291aed92fa6f013eca96437290c4c97c4cd9
pdf-font-stream PDF embedded font (sfnt) at offset 0xC913 10880 bytes
font_01_sfnt_off0000e222.bin
11833209517ba63fd47fb063044dbc18945dde3a360274c4806f49d48f08e503
pdf-font-stream PDF embedded font (sfnt) at offset 0xE222 17160 bytes
font_02_sfnt_off00010e80.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E80 16792 bytes