Malicious PDF — malware analysis report

Static analysis result for SHA-256 c89f0317ab9bfdc8…

MALICIOUS

PDF

74.6 KB Created: 2021-10-02 21:06:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: a3ccd55d6db057e880f6ef66287fdb43 SHA-1: 0bdf75f989e77370979a94bd2dfe01665d7a33c8 SHA-256: c89f0317ab9bfdc87b80c2e758fd78db43b69e1c5ceafddd9d829a6af55cb540
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest this PDF is malicious, likely serving as a lure for phishing or malware delivery. No scripts were extracted, but the heuristic findings point to exploitation and potential initial access via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://garglob.ru/uplcv?utm_term=assassin%27s+creed+rogue+ps4+trophy+guide PDF link annotation
    • http://brno-skoleni.cz/ckfinder/userfiles/files/56484128513.pdfIn PDF document text
    • http://wadirumshootingstars.com/userfiles/file///65535636304.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/76960517084.pdfIn PDF document text
    • http://www.fd.ntou.edu.tw/ckfinder/userfiles/files/nurovugidejifub.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/adef1bfa5a0da7ca5af4df2ea82d473c/87217801238.pdfIn PDF document text
    • http://dragonspond.com/uploads/files/bubibefafafudesasa.pdfIn PDF document text
    • https://g4m3s-4p1-12s1.com/contents/files/90701525985.pdfIn PDF document text
    • https://cosonnguyenthanh.vn/webroot/userfiles/files/32470553882.pdfIn PDF document text
    • http://lemma-studio.pl/userfiles/file/jakupututerudakala.pdfIn PDF document text
    • http://ilkemymm.com/image/files/48492032955.pdfIn PDF document text
    • http://werder-ritter.de/UserFiles/File/pesonor.pdfIn PDF document text
    • http://titusauto.hu/kepek/file/pigijavimiwugu.pdfIn PDF document text
    • https://mklaassen.nl/images/file/27895875063.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16146d3a0e0f06---tesejefaxufituzeto.pdfIn PDF document text
    • https://ra7a7p-h3ba7.com/contents/files/28292637055.pdfIn PDF document text
    • http://foto-klub.dk/userfiles/file/93645521206.pdfIn PDF document text
    • http://demo-enriquemora.shopcloud.es/ckfinder/userfiles/files/tizegidekalajinolosaz.pdfIn PDF document text
    • https://xn--80ag1a2a.xn--p1ai/files/file/27241444354.pdfIn PDF document text
    • https://bgg.pirkitpadangas.lt/ckfinder/userfiles/files/lezogorusekatonin.pdfIn PDF document text
    • https://dimensioninteractive.com/WYSIWYGImage/file/duporixovela.pdfIn PDF document text
    • https://architektor.ru/uploads/file/vagofiduwosovodibomezu.pdfIn PDF document text
    • http://ecovn.vn/uploads/news_file/16972010243.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/31pvbp93rbe0cha4s8hos96d5l/lapilovukenoponal.pdfIn PDF document text
    • 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_off0000ba73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA73 19248 bytes
SHA-256: 802be4044abef8c7ec0ed03e2bdae13ba9f7d0a4bca27b5f0cdd1dc32ee774e8
font_01_sfnt_off0000eb2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB2B 11056 bytes
SHA-256: 97b0b28eeeca18a36d7d220f9eab43d176dcacd647f77dc024c80ab703534787
font_02_sfnt_off000104c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1