Malicious PDF — malware analysis report

Static analysis result for SHA-256 52d95626458d73c3…

MALICIOUS

PDF

82.8 KB Created: 2021-09-20 11:49:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 43b41d5b44513543bb9cf916de303d60 SHA-1: dfe8460259404c493f4aea4131a67248b9ccd1ab SHA-256: 52d95626458d73c38c2a0a65a80447d06c666eae8eef796e00d47c77aa0bf16d
96 Risk Score

Malware Insights

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

The ML classifier and PDF heuristics strongly indicate maliciousness, identifying the file as a link farm. It directs users to multiple URLs hosted on compromised CMS upload storage, suggesting an attempt to distribute malware or conduct phishing. The presence of numerous external URIs and compromised CMS upload links points to a coordinated effort to leverage these resources for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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 https://crysiq.ru/uplcv?utm_term=venom+russian+full+movie
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/4a7195fb6a0cffb9304bf0844f9b07cf/48997948005.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/daec78d6172b8590b661c2bcfff297ad/91508427854.pdf
    • https://ladangmimpi2.com/contents/files/75529834628.pdf
    • http://hodori247.com/uploads/files/luxadoxidabijajefeb.pdf
    • https://juvelyrikoscentras.lt/Files/file/17457533250.pdf
    • https://epponline.com/mentorfinancial/page_images/file/2573680552.pdf
    • http://driver-jazda.pl/upload/file/kilujabafivesefipujediv.pdf
    • https://primer-spb.ru/files/files/40404242890.pdf
    • http://bfcy88.com/uploads/files/32531409992.pdf
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161475dbd609d7---fudotofamofuleridizi.pdf
    • http://www.naturhalles.fr/fckeditor/userfiles/file/bufafugopitufunotijejinu.pdf
    • https://juniorclublivorno.com/sitonews/images_upload/files/japipive.pdf
    • https://milliondollardesiclub.com/upload_files/featured/files/kanegudutosativodix.pdf
    • http://hart-metale.pl/gimnazjum/userfiles/file/luneb.pdf
    • https://nayyaralidada.net/alpha/ckfinder/userfiles/files/xatatop.pdf
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161410cdee82d9---sirojijedaxupo.pdf
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613aafc47bb3f---nimefegepop.pdf
    • http://avalon-essenzen.at/userfiles/file/90944438567.pdf
    • http://humidorio.de/ckfinder/userfiles/files/pulewesubelexopuwipegobiv.pdf
    • https://www.bevillelecomte.ovh/ckfinder/userfiles/files/gufemafibiwakaketejigudal.pdf
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e488ca5cd8---3421779098.pdf
    • https://fgcrubochi.com.ng/ckfinder/userfiles/files/46576464487.pdf
    • https://snowcat.pl/admin/ckfinder/userfiles/files/fiwalekalobudamuxisata.pdf
    • https://jmclimatizacionhvac.cl/images/subidas/file/jijufuf.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_off0000de8c.bin
b6c0340320060fc0b0280778cc4d19872365e5a94c76568f870de268d8a05c48
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE8C 18244 bytes
font_01_sfnt_off00010df6.bin
96419a63a88abf5de74312b2888444abc5b367a920a5a9103be307876cd19f80
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF6 10412 bytes
font_02_sfnt_off0001258d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1258D 16792 bytes