Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ac1bcfc4b12eb19…

MALICIOUS

PDF

82.1 KB Created: 2021-09-17 01:33:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d3adece6918ac0e058d79351f835cbda SHA-1: f4bf9cf1dae458f265a9213f57e7f844dec0d56b SHA-256: 8ac1bcfc4b12eb1952f28e8c062ec216dc55fabd0428e2a9d37df92165c73164
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://oniceh.ru/uplcv?utm_term=update+hudl+2+to+lollipop
    • https://www.igescanada.com/ckfinder/userfiles/files/20290845379.pdf
    • https://flammerouge.ch/userfiles/files/fazawetimubidovudafifa.pdf
    • http://chronocertif.com/userfiles/file/mapukemobubutogegos.pdf
    • http://pilot-market.ru/new/files/file/63772138523.pdf
    • http://weighlessthisyear.com/ckfinder/userfiles/files/fafaxesaxanagotapanugebo.pdf
    • https://fundreamz.com/ckfinder/userfiles/files/26353843834.pdf
    • https://www.comperat-89.fr/ckfinder/userfiles/files/sabuzitoruwiganozigoxeb.pdf
    • http://armiikrajowej36.pl/public/upload/ckfinder/userfiles/files/rukoxojelusexigoxelanej.pdf
    • https://alpasol.e-giant.net/upload/files/pexan.pdf
    • http://hide-bo.com/img/tmp/file/58322980582.pdf
    • http://roomyab.ir/basefile/roomyabir/files/tadosefixogusipifi.pdf
    • http://xn--76-6kca8aqc6c.xn--p1ai/pic/userfile/badebewetogimevunes.pdf
    • http://jmyhship.com/uploadfile/files/70278444700.pdf
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/purc7tf4vrt0sqpl6v43k2d35m/65096955140.pdf
    • http://guoyangmoju.com/userfiles/files/25540334385.pdf
    • https://sausalito.com/wysiwygfiles/file/52450329445.pdf
    • https://yp05.com/_UploadFile/Images/file/puwaj.pdf
    • http://krasneclanky.cz/uploads/wefopetox.pdf
    • http://viorina-deko.com/images/file/wejuxikelaruliri.pdf
    • https://lenaoyunlar.com/calisma2/files/uploads/demufevobuwoxuzozonamebud.pdf
    • http://phunggia.biz/userfiles/file/92713650637.pdf
    • https://hunglivet.com/uploads/files/202109131909516321.pdf
    • http://classicalgardenornaments.com/uplds/file/93294741892.pdf
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/oofao43k0l5lmlgdjap5hgip21/wubawi.pdf
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f3c3da39e1---wezipenesi.pdf
    • https://gtnet-engine.com/ckfinder/userfiles/files/19489417344.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd09474e0a---guxopatexazekonovigajuvos.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_off0000dc5b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC5B 16792 bytes
font_01_sfnt_off0000f472.bin
e7a6ad47b4d868338969246fdca617abef5aab3aa4261232cad33a2ff8e99c97
pdf-font-stream PDF embedded font (sfnt) at offset 0xF472 10344 bytes
font_02_sfnt_off00010bf5.bin
0107ad1eb47e15ce8982f567125779f56f93474f34590c4c0c78e486b9baffe5
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BF5 17800 bytes