Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b20158ec17df0a8…

MALICIOUS

PDF

81.8 KB Created: 2021-06-24 14:38:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 714e766523b279e2b19ea38ddca95964 SHA-1: c2405b7a775119a572eb334e1d02c422515a0910 SHA-256: 3b20158ec17df0a86e7101ea0e4eb15cb2e0325c2085831482d2088050a61302
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as 'Pdf.Phishing.Trojan'. It contains numerous links pointing to compromised WordPress upload directories and other domains, suggesting it functions as a link farm to distribute malicious content or phish users. The embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://daycamhoa.net/upload/UploadFiles/files/97941488878.pdf In PDF document text
    • https://chupwo.com/editor_upload/file/xekujufoxanazegul.pdfIn PDF document text
    • https://gtselect.fr/ckfinder/userfiles/files/19197696500.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/99246793474.pdfIn PDF document text
    • http://english-life.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607211a8b51ad---mimage.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/975292a71fce707243f369afc726a5b9/16308435339.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/sefexapepe.pdfIn PDF document text
    • https://olgapopovaphoto.com/wp-content/plugins/super-forms/uploads/php/files/cfbe76e91e96aabb52f5dde0d02b8154/zijanujasamijakawexik.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d66f40cfec---gizidusu.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/47a6e24a65a51d01eadd83f11ee4cad8/javifox.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/24786648c315778a09db7be8b0b37763/menulisonajotipa.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cafdb2caf9---putonafidosotupegitun.pdfIn PDF document text
    • https://dm288.rs/slicice/file/43575982083.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/10092186423.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ac264ea33e9---4572436683.pdfIn PDF document text
    • https://hyundaia.ru/userfiles/file/2363202482.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=play+minecraft+bedwars+online+freePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f580.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF580 5288 bytes
SHA-256: f51030df4ba4fe7d61dc94188b272db03b69185dd6acfb4ff511186c33ff4062
font_01_sfnt_off0001076a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1076A 10716 bytes
SHA-256: 01cfacb0aeea77483c4f7d4bc08e6d9c8c5d6320645c5ec2fbb76c9c7ac2b2d7
font_02_sfnt_off00012c1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C1C 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333