Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5b4398b4a76d9f3…

MALICIOUS

PDF

84.7 KB Created: 2021-09-03 15:46:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 8be42a0acabfd5c26670f490cc497abc SHA-1: d524130af9b1ed99f104e8fc34f2432f77364ea3 SHA-256: b5b4398b4a76d9f30806b346e8f5995280e1ea4e4327601d605c60c642e99240
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution scheme. The PDF's structure and embedded URLs strongly indicate it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 https://chcial.ru/uplcv?utm_term=objective+proficiency+pdf+free PDF link annotation
    • https://millinerandassoc.com/files/file/53918304051.pdfIn PDF document text
    • http://tremonttemplemacon.com/clients/862779/File/ditunogogawine.pdfIn PDF document text
    • http://unionasset.net/file_upload/spaw_upload/file/20210902075720.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16071063aa9af2---37442849605.pdfIn PDF document text
    • http://tavio.su/files/file/33210446878.pdfIn PDF document text
    • https://sardavetri.it/userfiles/file/sijal.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/35eih5nlbuu8uhkpe1ar6qkda0/fiwexanaxazimon.pdfIn PDF document text
    • https://auto-rujo.com/images-editor/file/bofezi.pdfIn PDF document text
    • https://paron-rebondir.com/uploads/files/48784226128.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/cd1610a49059681881dfac3fa9c7ffb4/zipizoz.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/9b08738ca5dc28384e3185cbdba26fec/45272038086.pdfIn PDF document text
    • http://zeroseistudio.eu/userfiles/files/rovoxakapuwej.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/773004a652fab67338ce3e582bfd6f10/97919689527.pdfIn PDF document text
    • https://afayl.com/userfiles/file/fupejitoziva.pdfIn PDF document text
    • http://abpjseah.news-read.com/upload/files/tedapapidimiwel.pdfIn PDF document text
    • http://zionhillfirstbaptistchurch.com/clients/73368/File/890768479.pdfIn PDF document text
    • http://e-park.es/img/uploads/files/jimakipuvofagezid.pdfIn PDF document text
    • http://www.extramas.com/userfiles/files/munajokudojeru.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f383f4ac7d2---63556864713.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/bc386fecc4fd00314a24b473dbbc7dc4/nogokemaxona.pdfIn PDF document text
    • http://ajk-opakowania.eu/upload/fck/file/zapamezetad.pdfIn PDF document text
    • http://autoscuolemontagna.it/userfiles/files/93757482408.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_off0000e763.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE763 10712 bytes
SHA-256: 8e6767862cc9a7332b77f0e3747829cd916c81b8e58af81a291acd3ebfae2c87
font_01_sfnt_off0000ffde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFDE 17740 bytes
SHA-256: dd2197d64e1e90713bc432b133b91641b052d3be25190ea502bb4d567ad2f955
font_02_sfnt_off00012db6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DB6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1