Malicious PDF — malware analysis report

Static analysis result for SHA-256 56c17c130f15e020…

MALICIOUS

PDF

84.6 KB Created: 2021-09-18 13:12:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c79bd3e965846a8d771e7746c1dcefec SHA-1: d21412af80dcddeddec54300399eda3c72b8d77d SHA-256: 56c17c130f15e020cf006e3fb93e7010490b830151238efd4a87a1e308bdb32c
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external websites, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of embedded URLs and the heuristic 'PDF_RANDOM_URL_LINK' suggest the primary function is to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://queure.ru/uplcv?utm_term=how+to+stop+ads+on+phone+android PDF link annotation
    • http://ufnk.fr/app/webroot/files/file/84892736761.pdfIn PDF document text
    • http://virus-safe-zone.com/ckupload/files/75429912674.pdfIn PDF document text
    • https://osiindia.org/ckfinder/userfiles/files/76089348414.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/161392b28ed1ca---86243371368.pdfIn PDF document text
    • http://psn-monolit.ru/img_file/files/74209169842.pdfIn PDF document text
    • https://aakritidigitals.com/userfiles/files/37370927912.pdfIn PDF document text
    • https://eirai.org/editor/ckfinder/userfiles/files/26488144820.pdfIn PDF document text
    • http://volareinmongolfiera.it/userfiles/files/79927270228.pdfIn PDF document text
    • http://tajesink.com/Uploadfiles/files/4394509818.pdfIn PDF document text
    • http://bellamy.tw/uploads/files/202109050357569014.pdfIn PDF document text
    • http://lifeline-sports.com/files/file/65971760613.pdfIn PDF document text
    • http://huyminhplastic.com/upload/files/41750726731.pdfIn PDF document text
    • http://veewood.com/file_media/file_image/file/55217192507.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/dipojokudumuliwuso.pdfIn PDF document text
    • http://bodybybodyology.com/ckfinder/userfiles/files/93417050589.pdfIn PDF document text
    • https://teamcode.net/upload/files/88122660930.pdfIn PDF document text
    • https://tvsporedi.si/vsebina/varoselafexoz.pdfIn PDF document text
    • http://ambulatorioveterinariosantanna.eu/userfiles/files/11327728022.pdfIn PDF document text
    • http://short-story.ru/upload/file/16083411940.pdfIn PDF document text
    • https://igraonica.me/userfiles/file/39588582062.pdfIn PDF document text
    • http://formpart.com/upload/ckfinder/files/zamul.pdfIn PDF document text
    • http://dirpub.org/editor/ckfinder/userfiles/files/wekusiv.pdfIn PDF document text
    • http://utcsp.rustyramone.com/uploads/files/xafesimewitujuke.pdfIn PDF document text
    • http://tsradviseurs.nl/mailing/images/photo/file/fuvomewudi.pdfIn PDF document text
    • https://tes-sys.com/uploads/ckfinder/files/20210917/16318846653425.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_off0000e637.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE637 10520 bytes
SHA-256: 87cb3f56c0fd0cd5f69b392ef3b7e6c4d91d4a68366ba1cbaf9f941b15fab26a
font_01_sfnt_off0000fe22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE22 18032 bytes
SHA-256: 8680a231ec73735f0c783c62193e97baa12df2b22a2cb377204c96aa7e3bd16e
font_02_sfnt_off00012cf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CF1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1