Malicious PDF — malware analysis report

Static analysis result for SHA-256 92c4495ad73acf6e…

MALICIOUS

PDF

79.3 KB Created: 2021-07-21 10:09:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: d90556e7fbb78bafec34f85373db9ce1 SHA-1: abfbbcf206a7b76cfcf9e89b27f261042beef91c SHA-256: 92c4495ad73acf6e06288af036a572853e0f36076ba14e6cb8c0b25f0d8880d4
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to lure users to external sites. The document body is heavily obfuscated and unreadable, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://joewhitefamilysite.com/clients/59967/File/daremufekigiz.pdf In PDF document text
    • https://tavio.ru/files/file/48406571222.pdfIn PDF document text
    • https://grupahatak.pl/admin/_fck_files/file/29720303790.pdfIn PDF document text
    • http://landpas.pl/upload/file/zaxuvixuwiguxize.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c9985a51aab---72621162537.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a6464ce30bd---48916211477.pdfIn PDF document text
    • http://sport-way.ru/img/file/wusowunuluwisiga.pdfIn PDF document text
    • http://lempreintedubois.fr/userfiles/lempreintedubois.fr/file/fibuzujuduripoxib.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/ripukisafufukorutipab.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160716d150ac50---25963165685.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b09329c64c4---nujexanarovujidav.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/3bbef8828c9720290533326e804f2b90/silegujoputof.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160739072df44b---45767680644.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b4620df2fc---12169202736.pdfIn PDF document text
    • http://koszyczarek.pl/userfiles/file/baluvurekabomifizize.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/fukejoxiwebef.pdfIn PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/e2136a491a5b2e09b0fd28c62c59b877/14594455375.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/71725219595.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/vopuvofaf.pdfIn PDF document text
    • http://trekkingsapatours.com/upload/files/82869030087.pdfIn PDF document text
    • https://creteservices.com/FCKeditor/userimages/file/63249307261.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/kupukepewidure.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/6c9069654489f3b4d10c62faed7764e1/tufiserosakuwelo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=merge+multiple+file+types+into+one+pdf+in+c%23PDF 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_off0000d1f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1F5 17048 bytes
SHA-256: f7235aec96a4c99f149002923443a17c979cb6657fc3d9bb08a5e1566be86db4
font_01_sfnt_off0000fe75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE75 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001168c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1168C 11008 bytes
SHA-256: 86cdce1952e64aff80d1966fe66398a25f627d010dbf0a856465cb102ba6026e