Malicious PDF — malware analysis report

Static analysis result for SHA-256 c805d735e3f9309f…

MALICIOUS

PDF

90.9 KB Created: 2021-06-29 16:46:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1cc3a12eb15145f2f02d3fb8138b86d2 SHA-1: 0044face4c08dc001b774048a92df6b97b90f5a1 SHA-256: c805d735e3f9309f613793ad2719f5272465539e8802f2654096f9b62d651c79
164 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating it likely contains an exploit. The presence of numerous external URLs, many hosted on compromised WordPress sites, suggests a link farm designed to redirect users to malicious content or download further payloads. The heuristic 'SE_DOWNLOAD_BUTTON' further supports the idea that the document attempts to trick the user into initiating a download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://infrive.ru/uplcv?utm_term=essentials+of+ecology+4th+edition+pdf+free
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/blnr4jkr38l31hkm38ksc3s5s3/dezujenikumi.pdf
    • http://udaybharat.in/ckfinder/userfiles/files/fupivopipijaviwafuz.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca0c0bf9ac---90156451186.pdf
    • http://banquat.com/userfiles/files/58322798609.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/mlto4b5mu1d4n3ooal7f1gpe00/36870246246.pdf
    • http://amandatravel.com/userfiles/file/jixazenom.pdf
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16090328527cfe---91173094322.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe203462a3---paxewurovezemurikikuwo.pdf
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c5d5e0e6e19---65213257166.pdf
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16076ffde67efe---wugatevuzamazev.pdf
    • http://deurenhanger.nl/userfiles/file/wupewiso.pdf
    • https://remoteworkerclub.com/wp-content/plugins/super-forms/uploads/php/files/d528da0735d367557d2cc8641d629eab/89599879129.pdf
    • https://securitydm.com/slicice/file/65555692780.pdf
    • http://aksaaydinlatma.com/img/editor/image/file/7495760626.pdf
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c4216870a89---tikaxabedobilimarada.pdf
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad7bf6e0ae7---vikixenusi.pdf
    • http://gopherandsquirrelcontrol.com/admin/images/file/72029915167.pdf
    • http://baugeraeteverleih.de/benutzerdateien/vuzapu.pdf
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/dad6c920fa3a295ad35dd038f107c667/zugukolevifi.pdf
    • http://dekoblickfang.de/userfiles/file/zagoli.pdf
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/294062b063d7753d07eaa77a41802aa8/26610490758.pdf
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d77f7ac053b---safesizuxakugefunel.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b8ebf9e3a63---65523702231.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/6685is10mmbn5kgs6cimsu7s92/xibutunizipebalofefa.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_off0000fe79.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE79 16792 bytes
font_01_sfnt_off0001168b.bin
f6e36ff696b4bd3fabf57d586ae272a878e453cb69a73e69a6afd46138bde858
pdf-font-stream PDF embedded font (sfnt) at offset 0x1168B 17616 bytes
font_02_sfnt_off000144aa.bin
33ec085f95ac15b00a51397d2009db14de4c19172a2a799c28b9286f9d1077d3
pdf-font-stream PDF embedded font (sfnt) at offset 0x144AA 11076 bytes