Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5658be9f4941385…

MALICIOUS

PDF

70.6 KB Created: 2021-09-26 17:54:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: 40219a1407b6bc7fb9892d07a503ee22 SHA-1: 7895f9b9ff984e73516189d30e1e72dfa798ead7 SHA-256: c5658be9f49413856960384beda25c8e9b170b78fb9fd2e9c45ccc6b9e281d20
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs and is identified as a link farm hosted on disposable domains, suggesting it's used for phishing or distributing further malware. The presence of embedded URLs and the nature of the heuristics point towards a spearphishing attachment as the likely initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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=couple+games+play+store PDF link annotation
    • http://sea-cruise.ru/ckfinder/userfiles/files/26184196832.pdfIn PDF document text
    • http://ehomerealestate.org/images/file/2307550552.pdfIn PDF document text
    • https://inprovitvenezuela.com/ckfinder/userfiles/files/67848611549.pdfIn PDF document text
    • http://canadanur.com/resimler/files/gijifemuvametunirigagowo.pdfIn PDF document text
    • http://globalfeedindustry.com/upload/files/musopamebunut.pdfIn PDF document text
    • https://mraos.com/web/userfiles/file/67852516917.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613610d99bcda---gagabagajijerijebifagesi.pdfIn PDF document text
    • https://robertbah.si/files/file/77751342222.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/af346d642bf5793d7ab9580180d0a0a6/viwabadamilajovonitexo.pdfIn PDF document text
    • https://www.loscam.com/lib_common/ckeditor/ckfinder/userfiles/files/57811379450.pdfIn PDF document text
    • http://konstruktor33.ru/app/webroot/files/files/57976421477.pdfIn PDF document text
    • http://tonioloclaudio.it/userfiles/files/dulijadodisigowogevos.pdfIn PDF document text
    • http://parquet-cortes.fr/data/Files/dodazojakelupimena.pdfIn PDF document text
    • http://appinaris.net/ckfinder/userfiles/publics/files/fepobozigiwurerugi.pdfIn PDF document text
    • https://nonbodepsg.com/uploads/files/64039868778.pdfIn PDF document text
    • https://hohsingfiber.com/ufiles/files/68891222959.pdfIn PDF document text
    • http://mdknoodles.co/uploads/files/mikojajomuso.pdfIn PDF document text
    • https://sanaspinler.com/calisma2/files/uploads/womefigudipaguminetuxow.pdfIn PDF document text
    • https://ferdavagnar.is/images/fck/file/69902090387.pdfIn PDF document text
    • http://mygiftltd.com/userfiles/file/74997349487.pdfIn PDF document text
    • http://lafenicealcamo.it/userfiles/files/seziwowigudujisaso.pdfIn PDF document text
    • http://cn-polylysine.com/d/files/14337123898.pdfIn PDF document text
    • http://thongthien.vn/upload/files/16977271354.pdfIn PDF document text
    • http://thegioimercedes.com/upload/files/65285525400.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/39830107662.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_off0000b042.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB042 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c859.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC859 10644 bytes
SHA-256: eb17eea1a1902a174b4356ae7b462e5efed110a43a5560be67614a51aff6d67b
font_02_sfnt_off0000e0d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D9 16860 bytes
SHA-256: 91289297af113d35f33d95cc46b7ea81e5b362fc52f0f94469dfdf7dd45c6343