Malicious PDF — malware analysis report

Static analysis result for SHA-256 a01c722ce621ee7b…

MALICIOUS

PDF

85.7 KB Created: 2021-09-11 14:11:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e0473371dd8e04be4a7e1a28d8440a84 SHA-1: f2b057e92cb608b13dd6f15164d5fdf0eef2b9f9 SHA-256: a01c722ce621ee7bdc44717d3e6ab02182a7e7edc26704da7073d93d37f0ded0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of a link farm heuristic suggests the document's primary purpose is to direct users to a collection of other PDF files hosted on various domains. While no scripts were extracted, the structure and numerous embedded URLs point towards a phishing or SEO-based malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://whdhgs.com/uploads/file/20210905002416831.pdf In PDF document text
    • https://jewfri.kr/files/image/files/87803144398.pdfIn PDF document text
    • http://auksozvynas.lt/userfiles/file/xezufimaraled.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/87792683db7e5d1e0a15c720c78dd5a2/xanujajinafofitisupo.pdfIn PDF document text
    • https://swapnauraan.com/ckfinder/userfiles/files/satiwusojigotejuno.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/43529413281.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210902044701096.pdfIn PDF document text
    • https://mountainbrookbuilders.com/home/mountain/public_html/ckfinder/userfiles/files/melozasaredozami.pdfIn PDF document text
    • https://zerling.eu/nico/images/files/zavojixufajub.pdfIn PDF document text
    • http://alltechsro.cz/files/55458569969.pdfIn PDF document text
    • https://foundlight.ca/home/foun6192/public_html/files/custom_files/file/wuzikolijapifakolewi.pdfIn PDF document text
    • http://www.wiz-fac.com/uploadImg/file/5985642230.pdfIn PDF document text
    • http://www.tiendadelbordado.com/ckfinder/userfiles/files/kebiselabadokapu.pdfIn PDF document text
    • https://onlinendttraining.net/files/doputeku.pdfIn PDF document text
    • https://dalnoboy.com/data/filestorage/upload/files/vifowijezepolebi.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/g1t6ekta0cpo053rh4j90ivpb5/45732432987.pdfIn PDF document text
    • https://woodfur.in/userfiles/file/padukini.pdfIn PDF document text
    • http://nanopena.cz/upload/file/xafabaxututakures.pdfIn PDF document text
    • http://mobiliteit.nu/files/39015555054.pdfIn PDF document text
    • https://aydin-elektrik.com/resimler/files/pokugagarabuwimeli.pdfIn PDF document text
    • http://lyzjkgm.com/d/files/56556194291.pdfIn PDF document text
    • http://1544-7419.net/upload/fckeditor/file/42887714531.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/13546959277.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+send+a+video+from+an+android+phonePDF link annotation
    • 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_off0000e8e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000100f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100F3 18240 bytes
SHA-256: 54388480eb3db59ec46d6340748e3049bf92ab99708b4acdb83d698344730f87
font_02_sfnt_off00013055.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13055 10860 bytes
SHA-256: 73f6a4f67292358212640710c818ac47e909d217745dcf203d7ace33a94db136