Malicious PDF — malware analysis report

Static analysis result for SHA-256 a153384720d958f1…

MALICIOUS

PDF

70.1 KB Created: 2021-10-03 00:07:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c82499a605cd576e7b1112b6b6bf8094 SHA-1: 4cb6ccb4e897d39703b0e13dfe89505f6a65a72c SHA-256: a153384720d958f1a2cc11c8003929f946d0c8c6b3e1d7cfc70130c95322b59e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. While no scripts were explicitly extracted, the nature of the links and the detection names imply a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://gk-eventus.ru/admin/ckfinder/userfiles/files/bozarivuze.pdf
    • https://aadhaarretail.com/administrator/imagetemp/file/7971292370.pdf
    • http://acrclubinversores.com/files/galeria/files/76921920742.pdf
    • https://iqrainternationalschool.org/_assets/files/22789166240.pdf
    • http://ifa-astrologie.de/userfiles/file/bitugifi.pdf
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16145ae4d2a9ad---lagusefo.pdf
    • http://anbao.vn/uploads/userfiles/file/mijetepivusogolarozaxup.pdf
    • https://macauroommate.com/ckfinder/userfiles/files/fumopavan.pdf
    • http://caerulumpharma.com/upload/files/balemadelubamiga.pdf
    • http://tienphat.vn/imagesflashupload/file/25804907373.pdf
    • http://solamsys.com/userData/board/file/sarazuwigu.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/2a295fec7db6a250cee7eb6f1b3b2e56/pesikupe.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/958hhjotcsu4nsrsgordp5kpuk/21623390880.pdf
    • https://idealist.ro/userfiles/file/35261591373.pdf
    • http://oralrem.kz/ckfinder/userfiles/files/nawenadiditewate.pdf
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/53fc1c763a2b372ee79d0cb9ad33b66f/xepuvaxofebinimetuposoba.pdf
    • https://nexapos.com/upload/files/semozemumol.pdf
    • http://gildiamasterov.ru/userfiles/file/61029368297.pdf
    • http://zabradli-znerezu.cz/userfiles/file/xonezafapogifod.pdf
    • http://psychologadamczak.pl/userfiles/file/bufatexoginazi.pdf
    • http://bibikid.ru/upload/76054011260.pdf
    • http://taaltoetsvo.nl/userfiles/file/vuboteso.pdf
    • http://aroma-es.red/yamituki-n/uploads/files/4165659148.pdf
    • https://crownprolaw.cn/userfiles/Proj_Name/files/lenew.pdf
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210917_210543.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=denney+law+group
    • 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_off0000b327.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB327 16792 bytes
font_01_sfnt_off0000cb39.bin
0f2e5e3ca812ff89c5489a9497347c22e0406c402390ac7ebf9620bb978f13ac
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB39 15132 bytes
font_02_sfnt_off0000f1cb.bin
dd7e4d0d1cf70b6aafce4794acc132f6c2ff07dfda7f713807e0247442e1d067
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1CB 10372 bytes