Malicious PDF — malware analysis report

Static analysis result for SHA-256 4eb8996b1af2114f…

MALICIOUS

PDF

93.9 KB Created: 2021-09-13 21:17:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: cc6d1652d82d1b1264eb71d3b057e199 SHA-1: 96fc5ddd67ea61d0da81a54d661d219282e592f9 SHA-256: 4eb8996b1af2114f4a9c43fbb8f82bc1b8e02d698d0ce8db821bcc4e6dafefbe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple domains, many of which are hosted on compromised CMS upload storage or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself facilitates the attack by directing users to potentially malicious external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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://gostinica-domodedovo.ru/files/39573291469.pdf In PDF document text
    • http://aprt1day.ru/file/fejufaxaz.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/85072373718.pdfIn PDF document text
    • http://cukrarska-vyroba.cz/UserFiles/File/xaxeduzuxerinalave.pdfIn PDF document text
    • http://djapm.com/userfiles/file/52489907269.pdfIn PDF document text
    • http://rszm88.com/upfolder/e/files/20210910163414.pdfIn PDF document text
    • http://locum-system.pl/userfiles/file/73079327334.pdfIn PDF document text
    • http://omatsuri.kr/data/userfiles/files/barimililegerisex.pdfIn PDF document text
    • http://tienphat.vn/imagesflashupload/file/47464739456.pdfIn PDF document text
    • http://cauthangdep24h.com/upload/files/40404209213.pdfIn PDF document text
    • https://nvsrolko.org/ckfinder/userfiles/files/pivepesiguvek.pdfIn PDF document text
    • http://fairway.cc/images/blog/file/lasuwotavogimugepuji.pdfIn PDF document text
    • https://cristalensi.com/public/File/maturo.pdfIn PDF document text
    • http://vibrobreaker.com/files/files/kaliv.pdfIn PDF document text
    • http://e-baze.lv/images/site/file/voditoretufaniwawakokola.pdfIn PDF document text
    • https://festival.bg/fckeditorfiles/file/borosapaxemovimifexodoso.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/4d6b5dffdb7acb8103deca2c4bbe0f06/71793928848.pdfIn PDF document text
    • http://dienlanhlongan.com/upload/files/15708052467.pdfIn PDF document text
    • http://www.cerel.eu/images/wyswig_images/file/zodikepatej.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16133ca58a5cf8---58704295280.pdfIn PDF document text
    • http://spokoino.ru/i/upload/files/nofuduberobigokupewo.pdfIn PDF document text
    • http://sangiorgioautoservizi.com/userfiles/files/53834290536.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/c1b7882ebf45a47bd0a38fcd62084951/julolotiva.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=the+presidents+club+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_off00010ba5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000123b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123B7 17696 bytes
SHA-256: 9bfbd891f6ad6f19f134e67502185bebbe1541622591080aa6b20a02e85f5a4d
font_02_sfnt_off000151a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x151A6 10636 bytes
SHA-256: 428a487e8f93d46af4ac0329e41a5b158e4e220202038825179c3c5256609e06