Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1f016230e0e2223…

MALICIOUS

PDF

88.1 KB Created: 2021-09-13 16:15:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: efeb81f7e57421df0ad0b772e6871828 SHA-1: 72488999b5ac0316d7a7ba25a7fc22482805ac55 SHA-256: e1f016230e0e2223f6daef533dbadb228ba830411761b6d2763e02c47dad528e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to lead users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://eco-building.cz/UserFiles/File/43611753891.pdf In PDF document text
    • https://majubesar.info/contents/files/77848601065.pdfIn PDF document text
    • http://allamericannursing.com/userfiles/file/xofimu.pdfIn PDF document text
    • http://mrcookie.tw/upload/editor/file/030617252981.pdfIn PDF document text
    • http://pevak.info/UserFiles/File/fufijomelemoras.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/bb5a8836c6e785ea83bcd04a7ad98e6c/57893499553.pdfIn PDF document text
    • https://gjbuyerbroker.com/userfiles/file/xeviborediwi.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16138b9ef7a0e9---xuwuwama.pdfIn PDF document text
    • https://cambodiaangkorhomestay.com/userfiles/file/37324319031.pdfIn PDF document text
    • http://nasledie-sluck.by/var/upload/file/99627281171.pdfIn PDF document text
    • http://eca.or.th/ckfinder/userfiles/files/42810474940.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16134a6bbb8e48---roditenige.pdfIn PDF document text
    • http://madang.eu/f_pds/fck/file/reradabanavig.pdfIn PDF document text
    • https://heritagecambodiatravel.com/userfiles/file/renapupoxijodan.pdfIn PDF document text
    • http://ybshajiang.com/userfiles/file/2021-09-04/210904095026231539v3v7e8b8e54t.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/kowinimadurajoxa.pdfIn PDF document text
    • http://azs-szermierka.pl/zdjecia/fck/file/52374329753.pdfIn PDF document text
    • https://cheesykeju.com/contents/files/31909491079.pdfIn PDF document text
    • http://kocavietnam.com/upload/files/54020455528.pdfIn PDF document text
    • https://cmflower-kkc.com/ckfinder/userfiles/files/jixoguki.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210902133342.pdfIn PDF document text
    • https://siliconautomation.com/userfiles/file/xitadefuwivaruzujibon.pdfIn PDF document text
    • http://retco.ge/ckfinder/userfiles/files/xetomokosivigokozo.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/21699e9ab5ada82aac7ad478a32ac836/rumasavewow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=best+action+games+android+offlinePDF 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_off0000f5fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5FE 16904 bytes
SHA-256: a633f2f6ee2a9757d21bdede11516fe7f0caaa9bfa1fe7aa2569a3e41276096f
font_01_sfnt_off000121d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121D8 10872 bytes
SHA-256: ed60cbc8cddb56cdf27f8ae7c368538735b763a454e9b02381587ddce88f9ea0
font_02_sfnt_off00013ac4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1