Malicious PDF — malware analysis report

Static analysis result for SHA-256 d823725fa948bcf6…

MALICIOUS

PDF

85.5 KB Created: 2021-09-20 16:10:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4ef70aa79fcd7a517bcfabbec615eb19 SHA-1: d70af9c88d46f93e07e385c683d551cad3f445c0 SHA-256: d823725fa948bcf68198ec8ae9901efa784fdb5008a4c9aa1fe0010b88c11bb9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which are flagged as part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically phishing. While no scripts were explicitly extracted, the PDF structure and numerous external links suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://catamma.ru/uplcv?utm_term=the+shadows+between+us+read+online+free PDF link annotation
    • http://zap-interactive.com/uploads/files/31592797627.pdfIn PDF document text
    • http://av-jet.ru/userfiles/file/jigoxuzalizotoxekipul.pdfIn PDF document text
    • https://konzolstudio.ro/uploaded_files/file/vawogotuganalesubadonise.pdfIn PDF document text
    • http://webcertain.asia/contentupload/fckeditorUploads/organization_/file/wajagoritipa.pdfIn PDF document text
    • http://xn----7sbjvweekof5d.xn--p1ai/files/files/67502855301.pdfIn PDF document text
    • https://lanegarrett.net/userfiles/file/41643539915.pdfIn PDF document text
    • http://flygarfield.net/userfiles/file/lidezekalapubefixu.pdfIn PDF document text
    • https://hetodon.com/fckeditorfiles/file/89446079388.pdfIn PDF document text
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/68657915819.pdfIn PDF document text
    • https://www.aaptuk.org/ckfinder/userfiles/files/84681199039.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134d65d6f8cd---jubamisejakurotejimitan.pdfIn PDF document text
    • http://seanmore.com/userData/board/file/mumebufebep.pdfIn PDF document text
    • http://hidropro.hu/upload/90047909675.pdfIn PDF document text
    • http://bettaletroom.com/file_media/file_image/file/97799116489.pdfIn PDF document text
    • https://exclusivelimoservice.com/ckfinder/userfiles/files/wofekixike.pdfIn PDF document text
    • http://ferrocom-spb.ru/userfiles/files/fazusidawojago.pdfIn PDF document text
    • http://sistarelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jeruvijilenivali.pdfIn PDF document text
    • https://niboparis.com/upload/fckeditor/file/1631890602_1.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210907113414.pdfIn PDF document text
    • https://www.sonorisation-auxerre.fr/ckfinder/userfiles/files/zusutowilewomimedav.pdfIn PDF document text
    • http://obkladlazby.cz/userfiles/file/68926395922.pdfIn PDF document text
    • http://1-cities.com/blog_images/blog_/file/15535580067.pdfIn PDF document text
    • http://kramor.bg/userfiles/file/58623075471.pdfIn PDF document text
    • http://ayhancevik.com/images_upload/files/xuresomavetakebuv.pdfIn PDF document text
    • https://siahotel.com/userfiles/files/66855636777.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_off0000e8e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8E5 18084 bytes
SHA-256: 0fdda0e91458ffed7d90e3f505a8ca6c443e20c3a595d0c4226066c10c8bf254
font_01_sfnt_off000117af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117AF 10740 bytes
SHA-256: 6790b53d0aaffa8e5fc2600e61777555e5fb24a06c1f7e0e19b0b201250a911d
font_02_sfnt_off00013056.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13056 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1