Malicious PDF — malware analysis report

Static analysis result for SHA-256 11523bb24aee3dce…

MALICIOUS

PDF

80.7 KB Created: 2021-09-04 22:59:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: cce73a91afe772d74cc404006733cebb SHA-1: d1e3306545c170c4bd1c75fbe4cb32f200a39fcc SHA-256: 11523bb24aee3dcea77ece413d4d589332ef56748fd080c0a3df4d916b1b62f3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous links to external websites, many hosted on compromised CMS uploads or disposable domains, suggesting a link farm or redirection mechanism to malicious sites. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://bmcnx.com/userfiles/file/fimozuriti.pdf In PDF document text
    • http://cherishedmomentphotos.com/clients/8/84/84fe84b553acfcd191e166b7401b6f02/File/xuzotajowo.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/61fbb6b72a4ad35e98bd0a089094a06b/47400794132.pdfIn PDF document text
    • http://goraku-sangyo.com/userfiles/file/1467680802.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.com/ckfinder/userfiles/files/87134042090.pdfIn PDF document text
    • https://valubil.com/public/uploads/cms_file/cms_files/fotug.pdfIn PDF document text
    • http://burfel.ru/upfiles/files/dupebu.pdfIn PDF document text
    • http://boschvietnam.vn/files/usersfiles/files/kizixi.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608164a9ea828---rizaxukuzemojopinodulef.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///zabidosimizo.pdfIn PDF document text
    • http://t-p-fortune.com/userfiles/file/sejasipifisob.pdfIn PDF document text
    • https://12shio2.com/contents//files/25230702036.pdfIn PDF document text
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f583c2aa1a---1903173499.pdfIn PDF document text
    • https://fivetc.net/uploads/files/18720189904.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/0756c60cf646c974a4e8630b598ebbc4/3476397665.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fe25104ad3d---tarugitinowej.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/lekirijidakelisexunedewi.pdfIn PDF document text
    • https://cortemadera.com/wysiwygfiles/file/58249773522.pdfIn PDF document text
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/d79f99941faf17951224e342db9b66dd/52574678524.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609eefe54704f---xikejijixugetupobivos.pdfIn PDF document text
    • http://whs1979.net/clients/65916/File/rusilesog.pdfIn PDF document text
    • http://garderoba.sk/images/_file/10872612150.pdfIn PDF document text
    • http://bacsiha.com/public/ckfinder/userfiles/files/kidadusuvolarigiri.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=successful+grant+writing+pdfPDF 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_off0000d6f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF0B 17200 bytes
SHA-256: 4d505452de012f4e77c3a99351dd75c95ad0f61df23fb0c14a8e20fe508fd6dd
font_02_sfnt_off00011b8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B8B 10936 bytes
SHA-256: 9c0cadc1d47716306bd98f637e4ce778ddd089b4e01f3a7b21fe107c18c385c4