Malicious PDF — malware analysis report

Static analysis result for SHA-256 85d110ce4d129ace…

MALICIOUS

PDF

76.2 KB Created: 2021-09-27 16:31:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: d11a1219a351d7b29d62254e09e3a16f SHA-1: 3fc7c606188eb8f52761527fed3eff1d9b170acf SHA-256: 85d110ce4d129ace1396e5bdb38540d2a17560a280a1fcacb8f5c98f1370781c
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous embedded URLs, many pointing to disposable hosting and employing UTM parameters, strongly suggests a phishing or malware distribution campaign. The document body was unreadable, but the heuristics and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://wastran.ru/uplcv?utm_term=come+to+jesus+chris+rice+chords PDF link annotation
    • http://dj-maily.com/uploads/pages/files/dukamijodojoximu.pdfIn PDF document text
    • http://sisparts.pl/zdjecia/fck/file/xipibatakasozajexevat.pdfIn PDF document text
    • http://autoklej.pl/app/webroot/media/files/timomobo.pdfIn PDF document text
    • http://yeosingol.com/FileData/ckfinder/files/20210911_11F5B2B6F561B93F.pdfIn PDF document text
    • https://terminarz.online/kosmetyczka/krakow/files/29874048207.pdfIn PDF document text
    • http://artanuji.ge/admin/ckeditor/ckfinder/userfiles/files/suxidamozum.pdfIn PDF document text
    • https://hawkseyetravels.com/assets/ckfinder/userfiles/files/xukolozedalanabijivapul.pdfIn PDF document text
    • http://insightonafrica.in/userfiles/file/42099902354.pdfIn PDF document text
    • http://quocteanviet.com/img-chamthi/files/vuxojugu.pdfIn PDF document text
    • http://fatename.com/uploads/files/202109190233132934.pdfIn PDF document text
    • https://presstone.hu/userfiles/file/nafot.pdfIn PDF document text
    • http://ebara.com.hk/ckfinder/Zenith/userfiles/files/xakepiraped.pdfIn PDF document text
    • http://joltiy.ru/uploads/files/3395757547.pdfIn PDF document text
    • http://sbnjl.com/userfiles/files/86935129763.pdfIn PDF document text
    • http://danceaction.be/userfiles/file/73704728715.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/sezosubelivosapenozuw.pdfIn PDF document text
    • http://bourgogne.annuaire-regional.com/ckfinder/userfiles/files/pufomesufomazo.pdfIn PDF document text
    • http://horvathortho.hu/tmp/28163512578.pdfIn PDF document text
    • http://ipsaix.com/ckeditor/ckfinder/userfiles/files/fifonasesumusafumifopituf.pdfIn PDF document text
    • https://bharatbiodiesel.com/userfiles/file/xuruzakupenafuxewedewuwi.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613c368999ba4---83194703802.pdfIn PDF document text
    • https://flcevent.fcu.edu.tw/plugin/ce1/ckfinder/userfiles/files/20210919035156.pdfIn PDF document text
    • http://gazdalkodjokosan.hu/img/userfiles/file/44673624018.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_off0000be95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE95 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d6ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6AC 10584 bytes
SHA-256: da37c3ead809d569b90befe6960022673ac1051a12061581f22ea504776aaa4a
font_02_sfnt_off0000eed3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEED3 19988 bytes
SHA-256: e897f8af6c787a34b04f46ed6c499ebb871963f84b16a19dbc4c84c31593b2cb