Malicious PDF — malware analysis report

Static analysis result for SHA-256 99ce16c29807152c…

MALICIOUS

PDF

94.3 KB Created: 2021-07-01 19:43:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 528b4d1b6cf9f0ab4662ef18464b0b47 SHA-1: 49f88caaf2b7a404528bb098b914b3fafc29f525 SHA-256: 99ce16c29807152cb4922fb03e3890f4ff935382404a9df13b0e86ce632cd3be
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple compromised CMS upload locations, identified by heuristics like PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM. ClamAV also detected it as Pdf.Phishing.Trojan, and an ML classifier gave a high score, indicating a strong likelihood of malicious intent. The primary goal appears to be redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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 http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16077105773836---pofuridusopudevu.pdf In PDF document text
    • http://coffee33.ru/archive/file/57537892702.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c6c7e561b0f---33420056586.pdfIn PDF document text
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/ufosb7hf63hltvoounhc18n040/rezalamazomosaxum.pdfIn PDF document text
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/ec340594155140f4b4e099d8cc6826f1/wutexuvarutawuwe.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/10ae92f2045639cd4b9788b6e88db914/nemonimapoposamavawezun.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cdf7c30003---vewatuvoduvu.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/1fc78a24b33e4606d5075ff76601f5b8/bilebixividuzuvi.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160829c8cc1475---3315876939.pdfIn PDF document text
    • https://fanaf.com/article_ressources/file/misofokeripozobamot.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/9577fcca242cc2a6bea50a3c58d11cbd/79091875425.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/49006657911.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/d4d7e9acd2a6d22dc849000c558d8a8f/wiwininamezojo.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609cd1c580ec4---rotesup.pdfIn PDF document text
    • http://polyalpan.hu/_user/file/5954204464.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210430165110750501602.pdfIn PDF document text
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/9947b9c7b09cc3c86a32c2b11090fa2a/49832344908.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f7d30ad717---72368934100.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/sovejoropawobegilo.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/86bca1be1e970094cc240021229512e6/zubasitumefebe.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a656bead869---riregifuk.pdfIn PDF document text
    • https://songhong.info/userfiles/file/fadez.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/jijomokusakutomeva.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/r4405c0tng7dl7mlkfa7c46lmh/xirilipitipe.pdfIn PDF document text
    • http://miracleschoolministries.com/survey/userfiles/files/zuvamupexugo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=ultra+realistic+shaders+mcpe+1.16+downloadPDF 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_off00010aa1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA1 17776 bytes
SHA-256: f5d989f01dc7fae8a6ef2eaada6d71f02e4de35ef25e022e4e994c4d7d8dd83d
font_01_sfnt_off0001397b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1397B 11156 bytes
SHA-256: 24cec7a04e25c37d20deb8dd76ab3fc4541063d6bd1325a9a8afa26a97affc03
font_02_sfnt_off0001537d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1537D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1