Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a9c4b25bade91d1…

MALICIOUS

PDF

81.5 KB Created: 2021-09-03 15:38:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 91317bea1dfa2932db48ef67e48fd5a8 SHA-1: d9b940a387edf9ab3647a954a7cbfe9cc1374985 SHA-256: 4a9c4b25bade91d13655c456eddece72635f1aac4ecf6b28915b2a54f1c5bfa8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites, suggesting a phishing or malware distribution campaign. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, as these are common tactics for hosting malicious content. No scripts were extracted, but the embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 https://ketchas.ru/uplcv?utm_term=amhara+national+movement+pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/2c4f9c2bf48710a098230012394c8007/kelebuvitem.pdf
    • https://digireg.it/upload/rizidaturatobuzogi.pdf
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/q0fajhv5st6agju3m8604c9cub/woxefesotu.pdf
    • http://soldearenales.com/galeria/files/54606246278.pdf
    • http://efuegypt.org/userfiles/file/37429130970.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bddc257e9a2---xepujijokepedovujulakem.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160fc40672cd6a---padogulijebuzunox.pdf
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/da9853551122d31fb1fe8c19385712e8/65055841896.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e7902280c97---5791251028.pdf
    • https://alexandrapanayotou.com/web/images/static/file/67577169247.pdf
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/df18327e895b704821960f6aa7a494ab/xigom.pdf
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/20d2de82d1f995ed6438490d76c53ad6/xajoxugiboxupojofaboketu.pdf
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160729bb03616e---dapirawuradu.pdf
    • https://szekszardportal.hu/userfiles/file/23951240501.pdf
    • http://4bzsoftware.com/Images_upload/files/20207702219.pdf
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076392c97f98---79635276385.pdf
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091d05842d07---21577194825.pdf
    • http://hotstamping.pl/files/file/memebifejifanejew.pdf
    • http://getsolarnj.com/userfiles/file/berujiwagobuxaxevibola.pdf
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/germ259a4j6tqpquba5765h1rg/puvuposipuloluvize.pdf
    • https://giasusinhvien.net/upload/files/83918970884.pdf
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/4d4d2decb42e8b4872739af9c94dcb4b/42101631969.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_off0000d8df.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8DF 16792 bytes
font_01_sfnt_off0000f0f1.bin
c52370e152b41d51f5cbdef0a257da32a189afc1e7b4baac0bf4a969b57eec33
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F1 18300 bytes
font_02_sfnt_off00012081.bin
a6d134ee78e84fd311065ff7406f906440fbb3fa171c61089a96d5f282a4d41c
pdf-font-stream PDF embedded font (sfnt) at offset 0x12081 10640 bytes