Malicious PDF — malware analysis report

Static analysis result for SHA-256 18d2cf5f3434d624…

MALICIOUS

PDF

73.2 KB Created: 2021-09-22 13:12:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 1c36721539e633845c2d807a0d0ddf36 SHA-1: 976005cdc5bc87cffbe334e00317d6fc906932e9 SHA-256: 18d2cf5f3434d624e12751550eb54c159bcf4bbce9f0c8d32cdab110864a381d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document identified as malicious by ML classifiers and ClamAV. It contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious content or phish users. No scripts were extracted, but the PDF structure itself is indicative of a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c996f24884aad39918111cf7dc74f211/zajebekawe.pdf In PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ad424bfcac---fupajobijobetilirof.pdfIn PDF document text
    • http://picart-personal.pl/fckupload/upload/file/68629931312.pdfIn PDF document text
    • http://solar-makernavi.com/ckfinder/userfiles/files/dagiriwozomenuvifupuw.pdfIn PDF document text
    • https://brawlcall.jordanadams.com/ckfinder/userfiles/files/50168107318.pdfIn PDF document text
    • https://dermatologie-francophone.com/userfiles/file/85768862727.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd57b5a1ea---xeterabewak.pdfIn PDF document text
    • http://stauarchitetti.eu/userfiles/files/60396894308.pdfIn PDF document text
    • https://estoniapools.com/contents/files/dububobiwe.pdfIn PDF document text
    • https://albertscience.com/ckfinder/userfiles/files/dibidavelubudugi.pdfIn PDF document text
    • https://ycb.one/pro_pic/files/wiloxuwizipa.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/79e6bd6ed8787c96702379bc059fd2a4/saxubexa.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/23d520495cef18e41773021061c59025/94549000495.pdfIn PDF document text
    • https://ncvpte.in/userfiles/file/96353137931.pdfIn PDF document text
    • http://chalappuram.com/userfiles/file/mizewimitopa.pdfIn PDF document text
    • https://tonere.shop/app/webroot/files/userfiles/files/segegupajobupeb.pdfIn PDF document text
    • http://htbestcomputer.com/media/ftp/file/xesuvivozejikudaxaxola.pdfIn PDF document text
    • https://alhasooncorp.com/Files/files/vifufugilowagineseki.pdfIn PDF document text
    • http://coolscape.info/images/files/pilikunaxibozumuxi.pdfIn PDF document text
    • http://urjabatteries.in/userfiles/file/5127879815.pdfIn PDF document text
    • http://change4best.ru/upload/file/71109338421.pdfIn PDF document text
    • https://hotnews.md/upload/userfiles/files/xifemadutomiwefo.pdfIn PDF document text
    • https://sammycar.ch/sammy/sites/default/sammyfiles/newsletterfile/mobenubunakepeko.pdfIn PDF document text
    • http://trevelsi.ru/ckfinder/userfiles/files/3890134538.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=given+the+movie+eng+subPDF 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_off0000bca0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCA0 16456 bytes
SHA-256: c55621d7b87a50f23141b39e7b5359b70cfc1b54c1b03658c15745118614c9f7
font_01_sfnt_off0000e71e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE71E 10592 bytes
SHA-256: ff887a3748ea1808befb74806bd741a37f9c4ca251296b1c5309c326ef63e209
font_02_sfnt_off0000ff31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1