Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f8e4ef457c4e3b6…

MALICIOUS

PDF

84.5 KB Created: 2021-07-14 08:14:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c0f7a0c62ec45b4d0bc7d3f480e83060 SHA-1: d71dc2b27abfb5350c6fea75885fbb47f7a616c5 SHA-256: 0f8e4ef457c4e3b6ea6971c8e3e689ea34e176d40f6a78d6b3c40089bf1228b2
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous websites, many of which appear to be compromised WordPress installations used for hosting malicious PDFs. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The document body is unreadable, but the heuristics and URLs confirm a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://snnet.kr/board_pds/fckeditor/2021/06/file/59877942120.pdf In PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/4vaj7rgo1nvvvte6fnq9b8ocig/21217838774.pdfIn PDF document text
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/zukepomaremefi.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/6a4c9f9ac62521de42c8eb70ef8bbbbb/palazubofowebazunes.pdfIn PDF document text
    • http://bettaletroom.com/file_media/file_image/file/kowuwozowibonezixoza.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070dafc31084---mikitadolexabagebaro.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609fe3e936df8---fubapoxubiwalu.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607757a4186e0---40897569585.pdfIn PDF document text
    • https://michelbarbot.com/upload/files/xonetuxarivosijigozejosib.pdfIn PDF document text
    • http://whatdwellswithin.com/file/kubulodazox.pdfIn PDF document text
    • https://suprizpin.com/calisma2/files/uploads/karujom.pdfIn PDF document text
    • http://ural-kip.ru/admin/ckfinder/userfiles/files/64848312975.pdfIn PDF document text
    • http://divorce-difficile.fr/userfiles/file/nixetizuxokeserul.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/a785d3c676e403d2edc06c2dbb3b370a/sebazeg.pdfIn PDF document text
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/2b6c816d4b841a245301f2e36889d301/22271728153.pdfIn PDF document text
    • http://szrealty.net/uploadpic/2021-5/file/2021051609275973499.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afda7b8dc60---vobuti.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/76822122599.pdfIn PDF document text
    • https://sunarchegypt.com/userfiles/file/6220127103.pdfIn PDF document text
    • https://fgcrubochi.com.ng/ckfinder/userfiles/files/60111267413.pdfIn PDF document text
    • http://hotelniagararimini.eu/userfiles/files/63516792045.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608faac302b03---govexilunebizujatawifaviv.pdfIn PDF document text
    • http://sistersaviopublicschool.com/userfiles/file/18399208876.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7931373754---tulekug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=regression+analysis+by+example+chatterjee+pdfPDF 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_off0000e2d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2D4 17696 bytes
SHA-256: f04796e2ceb1f0941e8c39a62f1fd36a8c2ea46418f76d2409ee5496d0e603bd
font_01_sfnt_off0001118a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1118A 11596 bytes
SHA-256: d53dd52f4e4a7a5cc566251c0dcbc10eeeafb2011caab5cdf2e4ae7ad1800548
font_02_sfnt_off00012c79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C79 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1