Malicious PDF — malware analysis report

Static analysis result for SHA-256 7e371dd8e5ae1ef6…

MALICIOUS

PDF

77.2 KB Created: 2021-10-05 23:31:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: f9f00946305a367d51812aff6eebf197 SHA-1: 7228e6cc1dbc19a3e8171e2ec8fc45ba8926088c SHA-256: 7e371dd8e5ae1ef6c3f6261c48cda369d42702a6b41b3d104d300139eb71813f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It functions as a link farm, containing numerous URLs that point to various websites, including those hosted on compromised WordPress installations. The presence of multiple links and the nature of the hosting suggest an attempt to distribute malicious content or phish users.

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://oskarmak.com/userfiles/file/14856426737.pdf In PDF document text
    • http://oawebserver.com/piceditor/file/22995023259.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/i56hqe8mdaj7vh7rel6ajg0936/47873979629.pdfIn PDF document text
    • http://hadt.vn/upload/files/75130932861.pdfIn PDF document text
    • http://jjburgerut.com/uploads/files/34795429527.pdfIn PDF document text
    • http://www.polni.si/Images/files/27398150195.pdfIn PDF document text
    • http://redigonda.it/userfiles/files/54979496162.pdfIn PDF document text
    • http://goodwill.pl/userfiles/file/norevatibevilub.pdfIn PDF document text
    • http://extintoresorigen.com/images/editor/43073424394.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612eeb0716959---45405741567.pdfIn PDF document text
    • http://wskinbody.com/data/boardData/files/kekuwozudilatu.pdfIn PDF document text
    • http://hgbs.de/userfiles/file/negot.pdfIn PDF document text
    • https://shturnev.com/files/foFKED/file/kumorirawam.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16133f977a07a4---lafam.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/5aece02170b52e048a791e417972227d/34367851193.pdfIn PDF document text
    • http://homeopathyhk.com/files/35874878597.pdfIn PDF document text
    • http://z-sinpro.com/upload/files/91868339462.pdfIn PDF document text
    • https://www.osteopathe-montpellier-sud.fr/ckfinder/userfiles/files/relewamikujuvo.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/16156bf0736aa8---ruwafafagijo.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/files/rurogawavudesanejudo.pdfIn PDF document text
    • https://chsromania.managenet.ro/images/file/78119745381.pdfIn PDF document text
    • http://puzynowska-kancelaria.com/userfiles/file/zuzop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=moving+crossword+cluePDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c9d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9D8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e1ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1EA 17780 bytes
SHA-256: 51ec9256b645c514baf63c91abe3bd70af8f4cbdf6aa8afb45052bd0d15b3cef
font_02_sfnt_off00010f2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F2F 10532 bytes
SHA-256: 954929b4473969c52f25b28a81ba1099605cf3a67138746907fecd93f9b2b1d8