Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdd841bc3ad57919…

MALICIOUS

PDF

78.0 KB Created: 2021-09-19 02:51:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3e93739e011bc618571c47df42c42d8d SHA-1: 123b0f1e47c05fad8b3cf3bf77cf3e3fb2492472 SHA-256: fdd841bc3ad5791968ba095b9d8f4d2b95382e207904e8ccceb9c90b070ca249
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS uploads, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • 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.
  • 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://catamma.ru/uplcv?utm_term=purpose+of+rom+in+a+computer PDF link annotation
    • http://fujieshubao.com/zk/UploadFile/file/2021091802064273499.pdfIn PDF document text
    • http://propertiesforrent.com/userfiles/file///84079596958.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/62692623726.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/3pmrnckd5i2hu0fd8vi4h0r665/vefuso.pdfIn PDF document text
    • https://alwaysthesame.pt/site/upload/file/8982183973.pdfIn PDF document text
    • http://www.koeru.eu/failid/file/niliditope.pdfIn PDF document text
    • https://volpatoebrum.com.br/_common/admin/scripts/ckfinder/userfiles/files/tupejo.pdfIn PDF document text
    • https://pima-alarms.net/slicice/file/11055941734.pdfIn PDF document text
    • https://toananhmedical.com/uploads/files/74012138018.pdfIn PDF document text
    • http://inbeeldt.nl/userfiles/file/gaxufumepomefopukabuti.pdfIn PDF document text
    • https://franchisefarm.franchiseharbor.com/files/files/mizakoxojugexenoweziwipu.pdfIn PDF document text
    • http://optimumnieruchomosci.pl/uploads/userfiles/files/digiruxetuxogasep.pdfIn PDF document text
    • https://comfort8889.com/upload/files/pugawejepekixebokaxu.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/xatosometikugodobik.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16143efbd58f5f---98832330709.pdfIn PDF document text
    • https://zlatartopalovic.rs/files/33163628727.pdfIn PDF document text
    • http://wordtmann.beckbauer.eu/ckfinder/userfiles/files/49083927000.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/4lc237bailas0aok179n7i83ck/60685933440.pdfIn PDF document text
    • https://markmont.eu/editor_uploads/system/files/10356370672.pdfIn PDF document text
    • http://pilanatofishing.com/home/sandbox/domains/shelter.sandbox.tritek.hk/public_html/ckfinder/userfiles/files/37844230498.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613db6fb6a6a1---fexil.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_off0000cdee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDEE 10696 bytes
SHA-256: ee429dd0de3694965c619e865f58c9dd48e0ee2bfd8d10faf3d2945562363d30
font_01_sfnt_off0000e67e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE67E 16876 bytes
SHA-256: ca3e23b25887d55f2845eae692a74074b900beda4c5dde8936e7b894c6c568c6
font_02_sfnt_off00011245.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11245 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1