Malicious PDF — malware analysis report

Static analysis result for SHA-256 4152cbd8568e851d…

MALICIOUS

PDF

82.5 KB Created: 2021-09-17 17:24:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 230e9f6e5df9fc0766d8e678951629ed SHA-1: 4034a0f60e807b839ae50f62529fbbe6cb0c8556 SHA-256: 4152cbd8568e851d614b02197084793134d218ceaa57e258e0e131390bc690b5
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links to external PDFs hosted on various domains, many of which appear to be disposable. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests a link farm designed to distribute malicious content. The ML classifier and ClamAV detection confirm the malicious nature of the file, likely serving as a lure for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://elateridae.com/images/FCKeditor/file/xobutawobunifabonel.pdf In PDF document text
    • http://www.taxivanclass.com/uploads/ckfinder/files/zesefutijojuw.pdfIn PDF document text
    • http://instalace-charvat.cz/userfiles/file/ginavupureramuwa.pdfIn PDF document text
    • http://mea-travel.pl/userfiles/file/taladerezuboxixeradu.pdfIn PDF document text
    • http://enewind.com/pliki/file/sopopulojenofunanulaba.pdfIn PDF document text
    • http://dieutrimun.myphamkangnam.vn/webroot/img/files/murexewerugesika.pdfIn PDF document text
    • http://cuborh.com/natelinhanew/js/ckfinder/userfiles/files/madoka.pdfIn PDF document text
    • http://aotwcasino.com/ckfinder/userfiles/files/68443034973.pdfIn PDF document text
    • http://zwickerfoto.hu/_user/file/27142415123.pdfIn PDF document text
    • https://habibitours.com/ckfinder/userfiles/files/30091996231.pdfIn PDF document text
    • http://tivatijapan.com/uploads/userfiles/file/90913389851.pdfIn PDF document text
    • http://pwmtqatar.net/userfiles/file/gokimenolomuvurileguboniw.pdfIn PDF document text
    • http://imdad-egypt.com/userfiles/file/dumilagubidofevumiwo.pdfIn PDF document text
    • http://geometracosentino.com/userfiles/files/pogujasenedovikur.pdfIn PDF document text
    • http://skupka54.ru/upload/m/wanalonogozozagemoduje.pdfIn PDF document text
    • https://vico-real-estate.com/ckfinder/userfiles/files/64666399349.pdfIn PDF document text
    • http://ambulatorioveterinariosanfrancesco.com/userfiles/files/58330847375.pdfIn PDF document text
    • http://abnig.friendship-match.com/upload/files/10406301266.pdfIn PDF document text
    • http://fittbikese.hu/files/file/67487094656.pdfIn PDF document text
    • http://archissimo.eu/userfiles/files/26129523457.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/16140ed51789b0---dexexanotewolowazi.pdfIn PDF document text
    • http://copingconversations.com/userfiles/file/burugiwugiri.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141db1f0b349---lolizikifejenuf.pdfIn PDF document text
    • http://agro-norwa.pl/userfiles/file/80831531653.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=sito+per+scaricare+applicazioni+androidPDF 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_off0000dcff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCFF 10644 bytes
SHA-256: 682f22d6602768ee55b2d25cfa617e44f80f4f424c1542d970b39d042dffcbfe
font_01_sfnt_off0000f57b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF57B 17208 bytes
SHA-256: d8ff6919efb778113e583e7ffa123a663d666c6456c033e67a3f02c62ef2bb59
font_02_sfnt_off0001226a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1226A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1