Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f5cf3a5ab6d9e1d…

MALICIOUS

PDF

67.3 KB Created: 2021-06-25 04:16:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: b990929b00eb9cf5d68f8a7046e2b1b8 SHA-1: 1ed517c05f47d13f6c5feb19c35db3177e852129 SHA-256: 6f5cf3a5ab6d9e1dbd4c86836307eb4c6a2542e782b36610bb5211509cbfe6fe
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://bancodevida.com/bancodevida/admin/images/image/file/jogawumajawad.pdf In PDF document text
    • https://medtek.vn/storage/file/tikizi.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/vevinefapinesonexid.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/49i9fuva52d8k2hkuqqdsh6cn0/78791736905.pdfIn PDF document text
    • http://yorktownhs1987.com/clients/57482/File/65691871299.pdfIn PDF document text
    • http://rayanchem.com/d/files/31580709579.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608369f37c1cc---fidutogufaxifewi.pdfIn PDF document text
    • http://farmina.ru/uploads/files/gexijoraz.pdfIn PDF document text
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/6e9ef09890844fe3799b2230f80f18be/64939114340.pdfIn PDF document text
    • http://longthinhphat.net/uploads/files/91640570882.pdfIn PDF document text
    • https://ajitcoatings.com/uploads/libirave.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a29211767eb---lugezitapuxabegi.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c7c2a148c2a---tiwevorewuginepusegunegar.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/796412b0f533c2aaff8144f6c9209352/41554265071.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/b8879d03505c5ebb715c673c4b2579cf/6995380091.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/3d159d7f48b42af550ea2ba37de1129d/2011845078.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d41136c9a7---72644419179.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/8k7lcb81fegruc4fljbvhjj1d1/95172263224.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=balaji+publications+chemistry+for+neet+pdf+free+downloadPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c676.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC676 5856 bytes
SHA-256: b45757e26841c052be98e85ed286dd4e1eae38e9da7c3e7811a38917598ab1c9
font_01_sfnt_off0000da4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA4A 11056 bytes
SHA-256: 1c5d54175846ebd2308b8853509ea308dbefdb81476935aea3637a32647bc130