Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef72e3dbfa76afa2…

MALICIOUS

PDF

77.1 KB Created: 2021-08-17 11:59:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fae7ba47e8803a95d13fa972ee5512a2 SHA-1: 07ded41d58225a1ee9754086cdbc5a2d2c56b6af SHA-256: ef72e3dbfa76afa2d90065061b7347e88b6748a0a4bed57b068e59e2f54fdc46
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The document functions as a link farm, containing numerous URLs pointing to compromised WordPress uploads and disposable hosting sites, likely intended to redirect users to phishing or malware distribution pages. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific user lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://braciszewska-klimek.pl/fck_files/file/wivudividotunapotolep.pdf
    • http://azizolace.cz/images/file/65887330812.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160964190c7641---gewumek.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f60e462d9c7---61262698602.pdf
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/kadabazaxuraded.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092158db012e---wazexavun.pdf
    • http://pzhjintai.com/upload/files/vemewufuxa.pdf
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16074c3a8c5c7f---34942615419.pdf
    • http://biemmecommerciale.eu/userfiles/files/fukimuvadovokefi.pdf
    • http://kfnmsz.com/upfolder/e/files/20210709114134.pdf
    • http://lamgi.pl/ckfinder/userfiles/files/tigurapuvatuwusuxogefogiz.pdf
    • http://thehigh86.com/clients/13680/File/paxelavowodolirededul.pdf
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/449a3488e4a2aa9369df492f17c09bdd/jogizaxuwaroligodufibig.pdf
    • https://cartolmania.it/file/62737081668.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608a7c2c38190---92652479285.pdf
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8d353036f2---18988427434.pdf
    • http://icltindia.in/userfiles/file/81728202195.pdf
    • https://alexandrapanayotou.com/web/images/static/file/54939452757.pdf
    • https://powermailer.in/userfiles/file/kenigidunakegadukatuxifu.pdf
    • http://e-hematologica.pl/users//file/kusis.pdf
    • http://domeinbeverdonk.be/assets/files/file/tebawajasuxarir.pdf
    • https://suprizpin.com/calisma2/files/uploads/39798718513.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=examen+de+admision+san+marcos+2020+ii+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_off0000c6d0.bin
fefe750dae146cc947501190882ebe5eb6a9c35b59f2df0edd4ec255b971f104
pdf-font-stream PDF embedded font (sfnt) at offset 0xC6D0 10964 bytes
font_01_sfnt_off0000e034.bin
cbfa87a69f057b3e88852d12ac2027cf3dcb21a156731073ac32c704b533ad7e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE034 17812 bytes
font_02_sfnt_off00010d14.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D14 16792 bytes