Malicious PDF — malware analysis report

Static analysis result for SHA-256 a008c314533f6d66…

MALICIOUS

PDF

78.4 KB Created: 2021-09-17 20:30:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 04d45779706d8a6371648a46f6ec1799 SHA-1: b85ee8e105a9bfa55c1239523f79a9c2b26b9611 SHA-256: a008c314533f6d6646144c1aeb3813acb3ac8d611df93f3665a065a00007b82d
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with a high-confidence heuristic identifying a link to an algorithmically-generated URL. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of embedded URLs and the nature of the heuristics suggest this PDF is part of a phishing campaign or a distribution mechanism for further malicious content.

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 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://krisoc.ru/uplcv?utm_term=velocity+vs+time+graph+examples PDF link annotation
    • https://dichvumayphoto.vn/webroot/img/files/nolup.pdfIn PDF document text
    • http://baschin-heizung.de/meineBilderAlbertGrundschule/file/83568526952.pdfIn PDF document text
    • https://taichielite.com/louis/taichi/ckfinder/userfiles/files/11794914168.pdfIn PDF document text
    • http://oshcongregation.com/userfiles/file/daxawivogifaxunarubodebus.pdfIn PDF document text
    • http://campbellelectronics.com/uploads/podawarafeliteladaze.pdfIn PDF document text
    • https://dangeloremodeling.com/nbloom/fckuploads/file/sagezopebanewe.pdfIn PDF document text
    • http://emons-verlag.net/testarea/cwsCMSlight/media/files/86256524424.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/3744807587.pdfIn PDF document text
    • http://www.eau-msu.ru/ckfinder/userfiles/files/88581325292.pdfIn PDF document text
    • https://kitapkaplama.com/upload/ckfinder/files/judariwajizi.pdfIn PDF document text
    • https://12shio3.com/contents/files/doralofusitedaponivufe.pdfIn PDF document text
    • https://pyccenter.com/images/Upload/file/88536144115.pdfIn PDF document text
    • http://realestatemiami.com/userfiles/files/surapazedesupepedoka.pdfIn PDF document text
    • http://gocchame.vn/app/webroot/img/uploads/files/60440363875.pdfIn PDF document text
    • https://pnlcoach.com/misc2/file/In PDF document text
    • https://childrencareandliteracysociety.org/userfiles/files/50581546380.pdfIn PDF document text
    • https://www.hosotte.com/ckfinder/userfiles/files/xopokukanizub.pdfIn PDF document text
    • https://seeyounow.net/userfiles/file/12228122085.pdfIn PDF document text
    • https://urbanshapes.in/userfiles/file/rasavopupadepa.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109141020299970.pdfIn PDF document text
    • http://www.egavilanes.com/ckfinder/userfiles/files/jedosem.pdfIn PDF document text
    • http://gdlejia.com/uploadfile/files/20210910_085645.pdfIn PDF document text
    • http://xageunion.com/userfiles/file/16782282395.pdfIn PDF document text
    • http://aotem.com/data/home/qxu1780220113/htdocs/uploadfile/files/75643463063.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_off0000ccef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e506.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE506 10968 bytes
SHA-256: 629432f7d54c0b3b7dfc67597abc5e5efab1baf2a6e12625fcb533432e6583f8
font_02_sfnt_off0000fe95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE95 17432 bytes
SHA-256: 7137d2be5500d4c75b4ce83275e2e57b9cd531c88bef51b6dc7dbba595fd9f3d