Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b259927d1e7a7ec…

MALICIOUS

PDF

84.5 KB Created: 2021-09-17 23:46:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 66fd50f0ccfd5e727fed757d8f6dd8e5 SHA-1: 17d85b4b1f3e46fc1d90c9eeece3ac5aa628fc52 SHA-256: 8b259927d1e7a7eca4ead398108df69dd40db77f2f02d666ace952ad3a20a088
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. The heuristics identified it as a link farm on disposable hosting, with numerous external URIs pointing to various domains. The document body is heavily obfuscated, but the presence of embedded URLs and the overall structure suggest an attempt to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://medvor.ru/uplcv?utm_term=scientific+formula+of+alcohol PDF link annotation
    • http://boki.hu/editor_up/69561783476.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/16141eb8bc80e1---wejulosemefevodavevuli.pdfIn PDF document text
    • http://mn-print.ru/ckfinder/userfiles/files/84742182731.pdfIn PDF document text
    • http://yaan121.com/uploads/files/202109091715319753.pdfIn PDF document text
    • http://transportdiverse.com/uploads/files/94428847372.pdfIn PDF document text
    • http://healingtown.org/userData/board/file/gowusofaza.pdfIn PDF document text
    • https://studiovizia.com/webroot/img/content/files/lulewovatibedojof.pdfIn PDF document text
    • https://hygradeinsulators.com/images/uploads/file/sufininewo.pdfIn PDF document text
    • http://shiraz.sk/ckfinder/userfiles/files/71247633275.pdfIn PDF document text
    • http://axwelindia.com/uploads/96345616126.pdfIn PDF document text
    • http://cbestdesign.com/ckfinder/images_store/files/21267835975.pdfIn PDF document text
    • http://vietnam-intraco.com/webroot/img/files/joburozevelelelivax.pdfIn PDF document text
    • http://lingvastar.z-i-g-z-a-g.com/userfiles/files/katejagofevonozusulux.pdfIn PDF document text
    • http://5lovestartw.com/CKEdit/upload/files/jexepojorosanopogikob.pdfIn PDF document text
    • http://salman-group.com/userfiles/file/dolavuxodipuzemepaxerokug.pdfIn PDF document text
    • http://votava2.altrodesign.eu/ckfinder/userfiles/files/15157706285.pdfIn PDF document text
    • http://lamekatus.com/uploads/ckeditor/files/4789806861.pdfIn PDF document text
    • http://dichvuhieuchuan.com/upload/files/35781249645.pdfIn PDF document text
    • https://aildf.in/userfiles/file/lojif.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/0fa57db0d77e78a8e9cc051978225874/rosiwaradewebavusekur.pdfIn PDF document text
    • http://hjhchem.com/upload/files/fowipunotime.pdfIn PDF document text
    • http://lapawan15.com/shop/fck_file/file/8352281237.pdfIn PDF document text
    • https://edubox.mn/uploads/users/0/files/2497454456.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_off0000e609.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE609 17776 bytes
SHA-256: 2116c5148f1331c406263c151654884f67575f411b8fd52edfd1ba51d0b7ade7
font_01_sfnt_off0001146a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1146A 10608 bytes
SHA-256: b305b92286ff6298f47da213246b90657f8b603ddf0ecf1d3730cdc38d382a94
font_02_sfnt_off00012c78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C78 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1