Malicious PDF — malware analysis report

Static analysis result for SHA-256 7ecc91388ac5ed54…

MALICIOUS

PDF

70.4 KB Created: 2021-10-03 09:50:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 045bad125eb63ee84f88f2fedc8566df SHA-1: d1254e881ebb416471b5b4919b10843ede9b1405 SHA-256: 7ecc91388ac5ed5443327b6194f84448b93145f7c4771b0b0fdb65d9daca78c0
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple external links, with one identified as an algorithmically-generated URL hosted on disposable infrastructure, indicating a link farm for distributing malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are consistent with a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://guruamardaspublicschool.com/userfiles/files/95865547088.pdf In PDF document text
    • http://skpizzasubs.com/uploads/files/84097869220.pdfIn PDF document text
    • http://colorfulmedia.de/fotki/fotki/file/71856842571.pdfIn PDF document text
    • http://jfac.kr/ckfinder/userfiles/files/96161681936.pdfIn PDF document text
    • https://thucphamtruongxanh.com/Upload/files/75241472489.pdfIn PDF document text
    • http://constantcontinuity.com/membership/data/files/70405767813.pdfIn PDF document text
    • https://fier-forjat-valimet.ro/ckfinder/userfiles/files/bixasedeja.pdfIn PDF document text
    • http://qdxqw.com/uploadfile/file/58999769621.pdfIn PDF document text
    • http://redactron.com/userfiles/file/mopuxutuwumef.pdfIn PDF document text
    • https://gospel-streams.com/asset/ckfinder/userfiles/files/99995449528.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/4df6som6ssjaedd59u1lv1p0jh/tuzenupawu.pdfIn PDF document text
    • http://bptramptour.pl/files/file/82312405113.pdfIn PDF document text
    • http://voyagevietnamlaos.com/hinhanh/file/85975844517.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/15934015501.pdfIn PDF document text
    • http://coiffurenais.com/userfiles/file/38322599601.pdfIn PDF document text
    • http://alde-pace.org/ckfinder/userfiles/files/loregemanipexejupo.pdfIn PDF document text
    • https://podimercrm.com/img/files/13506934686.pdfIn PDF document text
    • https://khyatiinfotech.biz/ckfinder/userfiles/files/gisunusigemoxixeguturo.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/161593c6da4220---88484917147.pdfIn PDF document text
    • https://smartmedia.ro/app/webroot/files/userfiles/files/94235016756.pdfIn PDF document text
    • http://lucidareemantenerepavimentifaidate.it/userfiles/files/vujod.pdfIn PDF document text
    • http://africareview.in/userfiles/file/luwemavowekomozip.pdfIn PDF document text
    • https://landatur.com/files/galeria/files/dujojanagefitiwuw.pdfIn PDF document text
    • https://at2-turbo-j3t.com/contents/files/bajozovalavufeja.pdfIn PDF document text
    • http://lighthouse-connection.at/myPix/file/76199072028.pdfIn PDF document text
    • http://cmrivestimenti.com/userfiles/files/29693651347.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=accounting+principles+12th+edition+chapter+6+solutionsPDF 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_off0000b165.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB165 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c977.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC977 15808 bytes
SHA-256: 6fe3fc710f1a09b8f7501fd04315793d206c4d4b754e5f21e1fcf8aee2cc3848
font_02_sfnt_off0000f182.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF182 11212 bytes
SHA-256: d4b328f20ab3e48c5ae957f31557b10ecdd2349bc810ac91edacfdb5d0ea1977