Malicious PDF — malware analysis report

Static analysis result for SHA-256 43f168ba51e0437f…

MALICIOUS

PDF

70.0 KB Created: 2021-09-15 19:38:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 051788a2729560e82dee34598664e286 SHA-1: 11c79fd03c97737f70dfd0fc9fd20a324866c9f3 SHA-256: 43f168ba51e0437f6b594e74d44f65956d7cb950dba615b3aa7990b4245e9066
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised or disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document's structure as a link farm, coupled with the use of UTM parameters, points towards an effort to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://cructi.ru/uplcv?utm_term=riemann+sum+right+hand+rule PDF link annotation
    • https://tasleemdubai.com/userfiles/files/petiwejawatenifed.pdfIn PDF document text
    • http://cistenivytahu.cz/upload/file/36889761754.pdfIn PDF document text
    • http://www.heksan.com.pl/file/21502578725.pdfIn PDF document text
    • https://sheenabusesandcoaches.com/userfiles/file/79929324898.pdfIn PDF document text
    • https://ta-taiwan.com/app/webroot/userfiles/files/tebimovi.pdfIn PDF document text
    • http://e-park.es/img/uploads/files/60656527598.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ee14fa8972---vupaloj.pdfIn PDF document text
    • http://timeyear-v.com/userfiles/file/52559429690.pdfIn PDF document text
    • http://52963566.com/upload/file/202109151724057427.pdfIn PDF document text
    • http://otestmanager.org/club/data/userfiles/file/20210912014500.pdfIn PDF document text
    • https://soosekszer.hu/upload/files/wuvidulakabapisatujuwelu.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/zebidosinepatalaten.pdfIn PDF document text
    • http://canphantich.net/Images_upload/files/goxexinupofeleb.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/e2c42427d3891a81256fbe73938af9e6/pimemozubopebezuwekixaw.pdfIn PDF document text
    • https://dichvuketoanvn.org/uploads/files/banonivolisowilominukeku.pdfIn PDF document text
    • https://solener.info/ckfinder/userfiles/files/zanemuvegir.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/79698674528.pdfIn PDF document text
    • http://saiprogetti.net/userfiles/files/39326741613.pdfIn PDF document text
    • https://totounited.com/contents/files/pefubonan.pdfIn PDF document text
    • https://szallas-karpatalja.com/upload/jivaporeregugewim.pdfIn PDF document text
    • http://emeat.ru/var/files/vugodumizikutugujeg.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/basutajufizamoguzep.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///nuxibolituburowuzorovikak.pdfIn PDF document text
    • http://szm.hu/userfiles/file/noxowirujowowibog.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/n528rjj080rk8h5fu1vm9in3a3/93446638859.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_off0000b058.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB058 15672 bytes
SHA-256: 5f00294b5baca5089404936a5e9a195f7aa8ffa165e5026e63700962724535f3
font_01_sfnt_off0000d86e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD86E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f085.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF085 10720 bytes
SHA-256: 3708de3ebcc2e0fe668e2ff56ff79e8acbbb1548831d3b26a44105dedc26aeec