Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4831242a2ab23bf…

MALICIOUS

PDF

81.6 KB Created: 2021-09-19 15:51:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 144aebe2080eab7d9c55a334e6810e10 SHA-1: b0d3ff8a2b719b9bf3c8f2b599785ff240852e3c SHA-256: e4831242a2ab23bf6a67310e13f071b37d9e956d3eaea21fb779e9d36ed67e92
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm. This strongly suggests a phishing or malware distribution campaign. The ML classifier and ClamAV detection further support the malicious nature of the file. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of malicious intent, likely leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://drafthe.ru/uplcv?utm_term=candy+crush+for+android+4.0 PDF link annotation
    • http://bobmeetin.com/media/galleries/files/4709112696.pdfIn PDF document text
    • https://ww150003.linebot.net/upfile/files/20210908070452.pdfIn PDF document text
    • http://fabtur.ru/upload/files/4362295980.pdfIn PDF document text
    • http://liderzy.natura2000.pl/imgturysta/files/rumerutanudipuriwawow.pdfIn PDF document text
    • https://drddvichitra.com/userfiles/file/40840168378.pdfIn PDF document text
    • https://ka-base.no/images_content/file/nonovejuto.pdfIn PDF document text
    • https://aalatour.com/basefile/b2caalatourcom/files/48301704966.pdfIn PDF document text
    • https://standsimulator.com/ckfinder/userfiles/files/6843465216.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612efb9e93f59---4598748754.pdfIn PDF document text
    • http://liceoadultos.juniorcollege.cl/userfiles/files/warefogurisubo.pdfIn PDF document text
    • http://webbsoil.com/home/webb/public_html/ckfinder/userfiles/files/40114650095.pdfIn PDF document text
    • http://csc025.com/userfiles/file/20210913182231_21paxh.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/2f05c115719a893a591db3c1073f1adf/2408542757.pdfIn PDF document text
    • http://protok.pro/upload/files/91303313017.pdfIn PDF document text
    • http://marinda.ru/pics/images/file/22194474767.pdfIn PDF document text
    • http://cobe-ing.it/userfiles/files/75082156134.pdfIn PDF document text
    • http://nextlab-semi.com/files/fckeditor/file/tuvijewevewuwireworuwa.pdfIn PDF document text
    • http://rickgrisolia.com/userfiles/files/mavusewelurukunuvegobe.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/kabajax.pdfIn PDF document text
    • http://www.somdattabasu.com/fckimages/file/bobovunadazof.pdfIn PDF document text
    • http://liga-stf.ru/i/upload/files/vitamowivameb.pdfIn PDF document text
    • http://computergramm.com/userfiles/file/wuzamenaxifovina.pdfIn PDF document text
    • http://embeddedhr.com/ckfinder/userfiles/files/94119619079.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_off0000d9c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9C3 10808 bytes
SHA-256: 699947ed8753e30109939da0684a15f91100cec8c4f4d8554fecdc9e04cf8d76
font_01_sfnt_off0000f2a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A9 17508 bytes
SHA-256: 69c75ee542a5ef3c5f5f376405f21011a515128ef11c5926a0c8dfaef6100d05
font_02_sfnt_off00012039.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12039 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1