Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7df27d2ded56c8b…

MALICIOUS

PDF

83.8 KB Created: 2021-09-20 00:51:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 81cdbd669729f7952561d67a4eb7f584 SHA-1: 78f74adbc71250f9d263e86aa59bcd943a23ada3 SHA-256: e7df27d2ded56c8bf33dab381835e21a5249f4bf1a6f21841710faebfb37284d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the nature of the links and the heuristic firings point towards a malicious PDF designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://catamma.ru/uplcv?utm_term=check+mobile+data+usage+android
    • http://jindi2010.com/uploadfile/files/wekanowogewedilomas.pdf
    • https://afra24.com/basefile/afra24/files/65299512244.pdf
    • http://www.anclupnapoli.it/userfiles/file/32660618125.pdf
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/8309caf7bbcbc9805818c50b00356a7a/sujotep.pdf
    • https://siroyensao.com/upload/files/42986837615.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/c15240edeff974b2b2dc0686ec262782/34966515057.pdf
    • http://omatsuri.kr/data/userfiles/files/50514014416.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/16130facc0fce3---gotifatevuxise.pdf
    • http://sanarina.de/ckfinder/userfiles/files/83034369057.pdf
    • https://bwhe.in/ckfinder/userfiles/files/88524877058.pdf
    • http://taiwanglassgroup.cn/userfiles/file/rixemuraguz.pdf
    • https://msvadba.ru/files/file/jotuk.pdf
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1613083c67ad92---rojijozona.pdf
    • http://ellenia3.eu/userfiles/files/1985715980.pdf
    • https://kvizek.hu/ckfinder/userfiles/files/kutewa.pdf
    • https://comobrew.com/newsite/images/user_uploads/file/64634150813.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16147a5fec65bb---42793443449.pdf
    • http://podhoru.cz/userfiles/file/12864026880.pdf
    • http://getdol.com/page_data/file/kewuseja.pdf
    • https://vr-spagna-20.effievirtual.com/galeria/files/7374481023.pdf
    • http://cerritos.songhakbbq.com/uploads/files/kamuwidogas.pdf
    • https://playindiano1.in/ckfinder/userfiles/files/22600423372.pdf
    • http://innova-perila.ru/upload/files/jukiwap.pdf
    • http://image.dlib.vn/libedu/news/bachviet/20210912/file/siwagimatifovawotu.pdf
    • http://circolonauticofavignana.it/userfiles/files/betadotoxosakabubemar.pdf
    • http://www.horakgolf.cz/ckfinder/userfiles/files/31086764687.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_off0000de4b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE4B 16792 bytes
font_01_sfnt_off0000f662.bin
4c19c5a4499d0a7592b1667d473dabdc2cb2ca0f1ebb3d4a2a19cf65ca9fdf8a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF662 11180 bytes
font_02_sfnt_off0001101e.bin
e220c042c9f141ad709c409ca0b13e4b6d32284b7ca04f359d19884d5b1308a2
pdf-font-stream PDF embedded font (sfnt) at offset 0x1101E 18800 bytes