Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0f7aaa8db671c67…

MALICIOUS

PDF

88.1 KB Created: 2021-09-18 01:06:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6d296b9c3eec0a54fd898cb8f021ffea SHA-1: f8db291a37bce6367af7ae2639044765fc4c92b3 SHA-256: f0f7aaa8db671c67f76054b216912d6579d9164642cfeed345e2508131c440e9
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, embedding a large number of external URIs, including 'https://catamma.ru/uplcv?utm_term=java+handler+post', which likely serve as lures for phishing or malware downloads. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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=java+handler+post PDF link annotation
    • https://insolite.lu/img/userfiles/files/juburirok.pdfIn PDF document text
    • http://knowleangling.co.uk/ckfinder/userfiles/files/viperigonuzegujagawopepum.pdfIn PDF document text
    • http://bortran.com/upload/image/file/20210910090647.pdfIn PDF document text
    • https://premium-house.uz/images/file/guruxoxeguzujawemof.pdfIn PDF document text
    • http://findusafranchise.com/files/files/tejemanimisugaparotewot.pdfIn PDF document text
    • https://ofly.om-digitalsolutions.cn/upload/files/suvorimalusekoredilapogor.pdfIn PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/22480555654.pdfIn PDF document text
    • http://lsmtrontractor.com/upfiles/file/20210908010441.pdfIn PDF document text
    • http://refah4ter.info/basefile/hotelrefah4terir/files/47783069345.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/b0d30b5981207d630fbeb84123a02006/92977416090.pdfIn PDF document text
    • http://fecoil.com/userfiles/file/xirixixudaki.pdfIn PDF document text
    • http://ecofincas.net/ckfinder/userfiles/files/84302613970.pdfIn PDF document text
    • https://www.thaiahpa.com/flash/files/10695461652.pdfIn PDF document text
    • https://ipekyolumedya.com/resim_galeri/file/80828139210.pdfIn PDF document text
    • http://montpellier-businessplan.eu/mbp/upload/images/images/upload/ckfinder/faxuruzukibonudet.pdfIn PDF document text
    • https://kangaroovietuc.vn/webroot/img/files/43812748130.pdfIn PDF document text
    • https://mercerapparelss.com/userfiles/files/70372196320.pdfIn PDF document text
    • http://kuryakyn.ru/userfiles/file/67247020218.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.de/userfiles/file/51475734689.pdfIn PDF document text
    • http://bulk-supplies.com/userfiles/file/didevepi.pdfIn PDF document text
    • http://cuboni.com/uploadfile/hong202109090346555065.pdfIn PDF document text
    • http://talentfuturesservices.com/sharpinstitute/images/files/18040445440.pdfIn PDF document text
    • https://apexsafetyproducts.com/ckfinder/userfiles/files/bubipiputirejovuxilew.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_off0000f669.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF669 17208 bytes
SHA-256: 018cef0a680c25c72ef58b2b25b34c0ae769775285c82f982cc75da1aecb423c
font_01_sfnt_off00012346.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12346 10452 bytes
SHA-256: 9b55dc81d6eeeb5bd97311070e960b603e847776dd23bb53ecbcf017e069919f
font_02_sfnt_off00013af1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AF1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1