Malicious PDF — malware analysis report

Static analysis result for SHA-256 16c5d0941a996039…

MALICIOUS

PDF

78.4 KB Created: 2021-06-22 22:20:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 1b9b0910f0890d18132c0351b3da6ce7 SHA-1: 1d6729705fe8b11f6b98b56f315b36495d1f16c0 SHA-256: 16c5d0941a9960397eae59582cb308db203052e48d132d90472a6ec85d313af0
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1204.002 Malicious Link

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a password-protected-archive lure. 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 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://inwebjor.ru/uplcv?utm_term=nfsu2+download+full+version PDF link annotation
    • http://volamtuyetthe.com/userfiles/file/45868442042.pdfIn PDF document text
    • https://binarbaidtrading.com/public_html/userfiles/file/zogitokupaxutenupoxodiga.pdfIn PDF document text
    • https://catwalkdogcome.com/editor_upload_image/file/fojenobefan.pdfIn PDF document text
    • http://18554080.com/userfiles/file/logubuvokutufuxamesole.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160946059340bc---xujosanoronizisujogewin.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/61217048551.pdfIn PDF document text
    • https://preprodpcb.com/userfiles/files/26108407956.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/65uf9mesg57nrpaorp6kl5fq3j/22729268729.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/ba0d3f5410307b0723c9a2207c59bd2a/jenavifiko.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160750f40b3237---17281805769.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609da63e9424a---tezuj.pdfIn PDF document text
    • http://nuovartea.eu/userfiles/files/2227881125.pdfIn PDF document text
    • http://xaydungphongphu.com/uploads/files/76363801039.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/bq3inkh798iurr8ssaaqh14ku5/kipikaxemokale.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607c7ed390fc1---wanoxozuzedijafadulimag.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/47501084840.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160978a0e1ae45---31358160072.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/4533672050.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e43a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE43A 4956 bytes
SHA-256: 7410b4949fecce654c5aa7852c7577f62574bf1985941b435b0ed3d48e43b4f7
font_01_sfnt_off0000f531.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF531 11732 bytes
SHA-256: 4cf1dd4ab32176c436f838e385c8c2efbf50822a6d37fc266252291655da71ef
font_02_sfnt_off00011ce8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CE8 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3