Malicious PDF — malware analysis report

Static analysis result for SHA-256 634c4acf6bb96fba…

MALICIOUS

PDF

74.5 KB Created: 2021-06-28 21:53:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 58b9298327820369411a49de89140b4a SHA-1: fe092cf1b54caac05dfd32afd0d7c60de811387b SHA-256: 634c4acf6bb96fba39f32e0e8f91600d34b0e537a238c2b5791e7121fa21f964
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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 https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/4d6ff41d392ef623b2f9d0ee60b9e551/loxorubetupomidetut.pdf In PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/f8a98c36e7f75dd6aef40e03244edf87/29929407817.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/a22364cae750608864741bb7126e0108/jexilibadaw.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/b580639732d4bba2ae23c730684899c8/38229034424.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16082a9e37bf43---86010357213.pdfIn PDF document text
    • https://samoinstitute.mn/uploads/assets/file/3241651602.pdfIn PDF document text
    • https://pametnidom.hr/pametne_kuce/userfiles/file/nudigapawud.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9a1691d115---13734737848.pdfIn PDF document text
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/b2b13f6e6cfb5e6c0c82d08b7bb4b64c/9749055315.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/qi1cjv7n7bdnnj78ps092knn86/gafobutanopobikuno.pdfIn PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/dcfec300f638f427e05d7a13666bd456/93861547638.pdfIn PDF document text
    • https://schilderlesvakantie.nl/ckfinder/userfiles/files/vowijixonesobozoxej.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160945b4e5be00---9878629999.pdfIn PDF document text
    • https://tsegypt.com/file/3322612585.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/kikizi.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6db953bee---sokamexanixowusifofekebat.pdfIn PDF document text
    • http://breakevenpoint.pl/uploads/editor/file/82458937542.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8846ec78c2---78723354246.pdfIn PDF document text
    • http://temple.mo/userfiles/file/kijezonosulunigekabamidi.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607e49bfd2b48---35631528887.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c0c717adcf---mowow.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2aadde14c---57234905010.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+insert+a+photo+into+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_off0000c28d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC28D 16152 bytes
SHA-256: b8dbf540a021c45676afad10b248df3d7909df1bc01294cc2ca2470a95cb46fa
font_01_sfnt_off0000ec44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC44 10628 bytes
SHA-256: 033ce19730202f64e380fc0aeca34c2c93998e9b7ca6d148090de2589e546311
font_02_sfnt_off0001048c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1048C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1