Malicious PDF — malware analysis report

Static analysis result for SHA-256 85656a40548af338…

MALICIOUS

PDF

75.6 KB Created: 2021-09-18 09:07:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f5c7887468b588eb7e58d8aefc2b209b SHA-1: 57f7756621ad7bb293d3cd80e41f07754fe9bb3b SHA-256: 85656a40548af33825c7b8ffd760963ceb50c8197bdac66e5bac06fa3f5a130d
126 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, with many pointing to disposable hosting, suggesting a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags this behavior, indicating an attempt to distribute malicious content or phish users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/16132bb2cd5b28---60738778717.pdf In PDF document text
    • http://agro-vostok.ru/userfiles/file/68223359741.pdfIn PDF document text
    • https://sunnyrosesschool.com/userfiles/file/36109720599.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/1cc9444d8fce4cfda5808ea149ea57ac/19212552121.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613b67f4231a3---xojuzojovelunidoxasosegal.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/161404ccf187b0---31409597916.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/sipawetojibojeg.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///lujimevodoguwupinegusa.pdfIn PDF document text
    • https://oncallanatomist.org/ckfinder/userfiles/files/tavonexuguwa.pdfIn PDF document text
    • http://goldenagegroup.vip/userfiles/file/gukexadewepotibeb.pdfIn PDF document text
    • https://goooinggroup.com/userfiles/files/20210904_010245.pdfIn PDF document text
    • http://vitali-schulz-eiskunstlaufen.de/userfiles/files/40648961039.pdfIn PDF document text
    • https://pisangmanis.com/contents/files/sededawizudijejuga.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/junekevexibogedik.pdfIn PDF document text
    • http://kfnmsz.com/upfolder/e/files/20210904235855.pdfIn PDF document text
    • https://h16hr15k-h19hr37urn.com/contents/files/tudopivosid.pdfIn PDF document text
    • http://sunnyten.net/userData/board/file/lufedetoxerugibuvijax.pdfIn PDF document text
    • http://www.poliklinika-hb.cz/userfiles/file/37475093165.pdfIn PDF document text
    • http://www.diplomat2014.ru/ckfinder/userfiles/files/sopofojamekulez.pdfIn PDF document text
    • http://webmba.fr/client/logo/file/bofagabum.pdfIn PDF document text
    • http://sweet-sugar.de/images/uploadedimages/file/zikolokutojuse.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/mojazagumebep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=ice+staff+code+bo3PDF 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_off0000c55b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC55B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD72 10388 bytes
SHA-256: cfc3163339ca3766f103586fcf1e85034c9a868ff8d309aa173f9df24a8ae740
font_02_sfnt_off0000f524.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF524 17152 bytes
SHA-256: 7aaae3e333ac3165b5c9023eb61f477d3ba0d9f32b87b689983f38fd5fa21604