Malicious PDF — malware analysis report

Static analysis result for SHA-256 155cb4add6690dab…

MALICIOUS

PDF

79.5 KB Created: 2021-09-16 07:58:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 38d80b5f77b2e6f527d1793a4b559184 SHA-1: 65da02a5ff4a6c2ffd214ac40085c7d23a7237b4 SHA-256: 155cb4add6690dabfd18fcaa957501f50296a3710ceae899df0add1efa16a445
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. The sample also exhibits characteristics of a link farm, with numerous URLs pointing to compromised websites and disposable hosting, suggesting an attempt to redirect the user to a malicious site. ClamAV detection and ML classification further support its malicious nature, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 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.
  • 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 https://irlanc.ru/uplcv?utm_term=running+man+latest+best+episode PDF link annotation
    • http://dreambeauty.kr/upload/fckeditor/file/lasovuzobalafexafufagejo.pdfIn PDF document text
    • http://exosportsante.fr/ckfinder/userfiles/files/22003069821.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/161355dcb899be---37372823802.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/94741855319.pdfIn PDF document text
    • http://oryginalnedekoracje.pl/userfiles/file/galeruxepuzeguvula.pdfIn PDF document text
    • http://sportgalaktik.sk/userfiles/file/lorepazasowukiso.pdfIn PDF document text
    • https://subded.org/userfiles/file/28577267538.pdfIn PDF document text
    • https://laser123.com/geektic/files/61007257107.pdfIn PDF document text
    • http://de.ruben.pl/ckfinder/userfiles/files/53689121435.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/rixiwuxosexigibipagulita.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c115b08765---kagibuwobodamifovige.pdfIn PDF document text
    • http://lionsmarsala.it/userfiles/files/vitesorumexamevez.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16142795711c31---gujifufulugoxuja.pdfIn PDF document text
    • http://greenhere.cn/upload/ckimg/files/202109031554228158.pdfIn PDF document text
    • https://nonbodepsg.com/uploads/files/60361492909.pdfIn PDF document text
    • http://wx-bm.cn/upload/ckimg/files/202109111449223482.pdfIn PDF document text
    • http://ultraljud.nu/bild/files/zopotefa.pdfIn PDF document text
    • http://gazosilikatnn.ru/uploads/files/vawetiwodazonuv.pdfIn PDF document text
    • https://toananhmedical.com/uploads/files/zekefeladetewotegigosif.pdfIn PDF document text
    • https://gkscam.com/userfiles/file/38262579529.pdfIn PDF document text
    • http://kingsauto-bar.com/js/upload/files/bedonuniforaxipigesakeg.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_off0000d073.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD073 10920 bytes
SHA-256: 1795d9ee39a04a1a6041257b119d8ca30f712b0cdcbfdca528f21220a534f436
font_01_sfnt_off0000e948.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE948 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001015a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1015A 18112 bytes
SHA-256: c6389048efab0abc84ffc760e8d70702b5c32d3ad48af10634852233df255cf6