Malicious PDF — malware analysis report

Static analysis result for SHA-256 79acb66fc7c5f32b…

MALICIOUS

PDF

69.4 KB Created: 2021-09-17 18:06:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3389886d1b1c5e5cb8701ef1020951ee SHA-1: 5a863ab99caec8687294550b71154300cdf25334 SHA-256: 79acb66fc7c5f32b6fd0c6a00a0bf2bd5fc463ad6edf17683266b23df92789a2
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links. The presence of embedded JavaScript suggests potential for further malicious actions beyond just linking.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161408b9b3116c---lugasexekomag.pdf
    • https://xn--80ag1a2a.xn--p1ai/files/file/96600408210.pdf
    • https://safrano.pl/userfiles/file/nebusozimarajudasukem.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1614212552b034---vomozivizezitawe.pdf
    • http://bresky.cz/res/file/pivufud.pdf
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/619bb52435ebb8032fcd6eecdd206dc7/muserat.pdf
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/44b0bb1dd2abb9a5842816e809a1b807/wafido.pdf
    • http://madinaboys.com/easydo%20v2.00/files/uploads/13611566120.pdf
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/fuselagajopaguraxikox.pdf
    • https://jyapa.com/jhuoyue/uploadfiles/kixezakupisukus.pdf
    • http://charontrade.hu/data/file/78485530901.pdf
    • https://eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/25253657562.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16137446b2f73b---11857521080.pdf
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/51454402566.pdf
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137a0c56d04e---48169927431.pdf
    • https://abogadosaccidentealicante.centralcms.cloud/galeria/files/wusuvabefusekeza.pdf
    • https://accuratesearch.com/userfiles/file/37690871773.pdf
    • https://alixdemassy.fr/userfiles/file/31994616709.pdf
    • http://usagimatur.com/files/others/nomatinejagusadeto.pdf
    • https://speakingparrot.com/upload/ckfinder/files/93664766131.pdf
    • http://lingvastar.z-i-g-z-a-g.com/userfiles/files/45504604702.pdf
    • https://ratco-hardware.com/Ups/files/mokobogamonom.pdf
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/271d5dfee77d44c0d70495d76492a68b/vigusijegaluzapavewete.pdf
    • http://terezszilvia.com/images/uploaded/file/xeralakuvovarifaba.pdf
    • http://www.leads-bd.org/app/webroot/js/ckfinder/userfiles/files/dososabebelesil.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=how+to+combine+pictures+on+android
    • 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_off0000b23a.bin
5dba8dd952d2be11fda654365713874479d5a430f0c91b6f0810a846f0834cf5
pdf-font-stream PDF embedded font (sfnt) at offset 0xB23A 14528 bytes
font_01_sfnt_off0000d6a3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6A3 16792 bytes
font_02_sfnt_off0000eeba.bin
1120aa17fc2868e6e35230ae8838d886f0d7cbf390e9169067a01de8e16b66e8
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEBA 10948 bytes