Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4d3fa134d9847bb…

MALICIOUS

PDF

83.9 KB Created: 2021-09-15 14:30:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d5ce59843b752e84f6829af5e6ecf9ba SHA-1: 6860b4d122ee476ab6af946af337c8ddc37ebcdb SHA-256: e4d3fa134d9847bb11652c3bcaa9022dcbf71af0456fb2abf6c51ecd2a3e2bcd
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to directing users to malicious content or phishing sites. The presence of multiple external URIs and link farm heuristics supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://tulga.ru/editor/files/41713900774.pdf In PDF document text
    • https://kapokcmassage.com/uploads/files/202109041029438467.pdfIn PDF document text
    • http://safarang.com/basefile/files/lekemazisezekelowemowu.pdfIn PDF document text
    • http://fusen-es.info/yamituki-n/uploads/files/53239230373.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/b54cdaa7b821ec37f6d0b33f3cf9db53/79054266708.pdfIn PDF document text
    • https://penmypoem.com/new/admin/uploadfiles/file/55597009603.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413359892e6---tidisotejera.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/data/editor/file/64333118259.pdfIn PDF document text
    • https://hoangnhataudio.vn/media/files/ripenutitarabogufowadu.pdfIn PDF document text
    • http://twtqedu.com/userData/ebizro_board/file/7005238776.pdfIn PDF document text
    • http://patrick-vallot.com/upload/files/kosekox.pdfIn PDF document text
    • http://sovaimm.it/userfiles/files/441165371.pdfIn PDF document text
    • http://borisovhlebprom.by/var/upload/file/xirusoxadutenap.pdfIn PDF document text
    • http://srmtteaparty.com/uploads/files/202109151646481291.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/28542385811.pdfIn PDF document text
    • http://wsm.hk/images/files/mopulotid.pdfIn PDF document text
    • https://ksuskalology.com/images/file/kidiviwawigezulalafute.pdfIn PDF document text
    • https://kocarbon.vn/luutru/files/luziluxo.pdfIn PDF document text
    • http://alhambra.kopanramen.com/uploads/files/fasivogigitamefunopodur.pdfIn PDF document text
    • http://xsjsbzrw.com/uploads/files/65307031121.pdfIn PDF document text
    • https://dammesliepas.lv/ckfinder/userfiles/files/84491875339.pdfIn PDF document text
    • http://purepassion.pl/userfiles/file/14655490067.pdfIn PDF document text
    • https://ww150003.linebot.net/upfile/files/20210913043206.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f5fd75c6b5---tivugetivopusosoruwuvaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=how+do+i+get+pokecoins+in+pokemon+goPDF 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_off0000dfc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC7 10720 bytes
SHA-256: d6b8bb80e3b52c89507fe567910ca01b215b15c9b2c950c43267c0663021706f
font_01_sfnt_off0000f82d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF82D 18696 bytes
SHA-256: d746153f0a47912b9f9565002068847f34e08000f7a272d88b0183ba480904a4
font_02_sfnt_off00012978.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12978 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1