Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b61de0a77a74b2c…

MALICIOUS

PDF

69.0 KB Created: 2021-09-26 03:25:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: d9182f78e6172ac7fa16866135316e18 SHA-1: 8a1f09f2fcc9d8dab9005147359f4bc63b848b00 SHA-256: 8b61de0a77a74b2ca4b5880d99726fa9e08f937ec443a6e33827c84cb495c319
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with multiple URLs pointing to potentially compromised WordPress sites and disposable hosting. The embedded URLs suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1614d8d29f33cc---sevirarevokejesasodorenog.pdf In PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/fffe4cfb4a79455c3944b9a76a457574/sedetodenozasajipozidital.pdfIn PDF document text
    • https://ikitellirezistans.com/upload/files/manuwugobavifa.pdfIn PDF document text
    • http://abwnickersonplaza.com/uploads/files/39000703099.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/manugudazuwutug.pdfIn PDF document text
    • https://cfacgroup.com/uploads/FCK_files/file/ninasuw.pdfIn PDF document text
    • http://architettotamborra.eu/userfiles/files/35913211330.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/38216259889.pdfIn PDF document text
    • http://autolavaggiocraparotta.it/userfiles/files/dogiviwagirazij.pdfIn PDF document text
    • http://twtipa.com/upfile/files/2021/09/09/fanuveziwuzud.pdfIn PDF document text
    • https://harkakotony.hu/UserFiles/file/51822130802.pdfIn PDF document text
    • https://natatourism.com/userfiles/files/midev.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/srobjmlsv2o0sk3j2a2ovm6mia/wifebobebumidonus.pdfIn PDF document text
    • http://xn--q20b13r9leepaeb.net/upload/file/202109140317225852.pdfIn PDF document text
    • http://hanboo.cn/Uploads/file/2021091904272870554.pdfIn PDF document text
    • https://www.pollackmihalyiskola.hu/ckfinder/userfiles/files/mekokoputesovad.pdfIn PDF document text
    • https://akvanova.ru/sites/default/files/15292342258.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/72c86aea0d1a894bec193888c9e83a45/rimore.pdfIn PDF document text
    • http://ark-mr.com/data/home/qxu2063190031/htdocs/uploadfile/files/19219460422.pdfIn PDF document text
    • http://kovospm.cz/fotky/file/tumajagenirazaw.pdfIn PDF document text
    • http://conhantaoankhanh.com/webroot/img/files/fasosajukadomurakexelizud.pdfIn PDF document text
    • https://yukkumpulgroup1.com/contents/files/74063099496.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=classic+chinese+poker+mod+apkPDF 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_off0000af87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF87 10804 bytes
SHA-256: 13b14093d29a69b48763b5dc66235b3af67c20b15541496f2cb9a349e3a680e1
font_01_sfnt_off0000c831.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC831 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e043.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE043 14952 bytes
SHA-256: b2d75f08ab50bd60fa8ffdf43d1891aa0921fe7b7b219961a6edb5bcd162f526