Malicious PDF — malware analysis report

Static analysis result for SHA-256 d33fbe4432247afc…

MALICIOUS

PDF

79.1 KB Created: 2021-09-14 06:22:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b0f74a12d1d513c19d1dbd105030e59f SHA-1: 4038027aa076241231a3c704c9228df799630779 SHA-256: d33fbe4432247afc76ffe3a4c64ff66fd24db5c667f81623b684368896a873c7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document's purpose is to host numerous links on disposable domains, a common tactic for phishing or distributing further malware. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://efckrakow.pl/userfiles/file/51069662117.pdf In PDF document text
    • https://jamuiboe.com/webroot/upload_media/67131605771.pdfIn PDF document text
    • https://gmnavarra.es/ckeditor/files/vazabu.pdfIn PDF document text
    • https://tidurmalam.com/contents/files/tovewafujaxaporuxusafugiz.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613accc7a8dd9---69123984354.pdfIn PDF document text
    • https://tmtteks.com/files/20153320093.pdfIn PDF document text
    • https://piti.leaddeehub.com/userfiles/files/57230235107.pdfIn PDF document text
    • http://drcleancenter.com/uploads/files/202109101809095184.pdfIn PDF document text
    • http://agriturismoilnoceto.com/userfiles/files/gimabonajibetaxoduze.pdfIn PDF document text
    • http://roocenter.ru/upload/file/kumariwezorusiwinibedo.pdfIn PDF document text
    • http://15441707.com/data/board/file/20210910043044.pdfIn PDF document text
    • http://hodori247.com/uploads/files/44646868189.pdfIn PDF document text
    • https://sintasyapi.com/img/userfiles/file/90877790304.pdfIn PDF document text
    • https://temahr.hr/files/86650040391.pdfIn PDF document text
    • https://cfi-registration.amyhalter.com/buzzboxgift/img/userfiles/files/nasozituxemufagewezatiso.pdfIn PDF document text
    • http://youil.org/userData/board/file/39938817644.pdfIn PDF document text
    • http://azs-szermierka.pl/zdjecia/fck/file/4839112867.pdfIn PDF document text
    • http://pet.nfe.go.th/m_site/ckfinder/userfiles/files/41413626273.pdfIn PDF document text
    • https://davidfoleyinc.com/userfiles/file/35161763463.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/1612f891a45df3---7147746887.pdfIn PDF document text
    • http://turagent007.ru/userfiles/file/12420801372.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/begojenojawurapufajunoke.pdfIn PDF document text
    • http://hide-bo.com/img/tmp/file/25338807647.pdfIn PDF document text
    • http://tractortools.cz/ckfinder/userfiles/files/13072599657.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=hypoglycemia+vs+hyperglycemia+symptomsPDF 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_off0000d014.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD014 17612 bytes
SHA-256: 7563168883b7f78215cb9a4508d243e5dad19a294f6bf6513401432b74a78801
font_01_sfnt_off0000fd13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD13 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001152a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1152A 10888 bytes
SHA-256: fa4cf86c82209520a7f61c3e095d847303653d0da43e61a012298b8f34847daa