Malicious PDF — malware analysis report

Static analysis result for SHA-256 4be30b5700e95962…

MALICIOUS

PDF

81.7 KB Created: 2021-09-17 00:59:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: bae098c7276fb5841fcc2c3b3299fabe SHA-1: d04fc467f2bca22deff5175026699fb3187c5f6f SHA-256: 4be30b5700e959624fb6d2f2695721e6e98b146d92a0df9d2402425da3ab18e2
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains a large number of external links, many pointing to disposable domains, suggesting a link farm or phishing lure. One high-severity heuristic indicates a PDF link to an algorithmically-generated URL, and another flags the PDF as a link farm on disposable hosting. While no scripts were explicitly extracted, the PDF format can embed JavaScript, and the presence of numerous external links suggests an attempt to redirect users to malicious sites for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 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://medvor.ru/uplcv?utm_term=cities+skylines+money+code PDF link annotation
    • https://aiwcecckolkata.org/FCKeditor/file/maniw.pdfIn PDF document text
    • http://newshop.jp/archive/file/xesobize.pdfIn PDF document text
    • http://quincy.pl/ckfinder/userfiles/files/67264763023.pdfIn PDF document text
    • https://darkoyunpin.com/calisma2/files/uploads/67283211866.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133571be1249---34072231123.pdfIn PDF document text
    • https://fundacjanadzieja.com/images/wyswig_images/file/voxebatejim.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16137dd4a391f3---92042336903.pdfIn PDF document text
    • http://ttmplus.com/userfiles/files/penaju.pdfIn PDF document text
    • https://smartmedia.ro/app/webroot/files/userfiles/files/zedoguvafopi.pdfIn PDF document text
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/75702042091.pdfIn PDF document text
    • http://cambridgekapurthala.com/damana/userfiles/file/66657028632.pdfIn PDF document text
    • https://granitnet.hu/editor_up/75315925819.pdfIn PDF document text
    • http://honghuibio.com/d/files/rigupesixel.pdfIn PDF document text
    • http://tid.vn/upload/files/numeniwirugolanot.pdfIn PDF document text
    • https://alyosserspneed.com/userfiles/files/fijok.pdfIn PDF document text
    • http://netflor.pl/upload/File/roxawubove.pdfIn PDF document text
    • http://sweet-sugar.de/images/uploadedimages/file/begisapigurovalotamubaw.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/dipofazimobiso.pdfIn PDF document text
    • http://elfuklid.cz/foto/Image/file/xanimepuzis.pdfIn PDF document text
    • https://liur-krd.ru/userfiles/file/paketazit.pdfIn PDF document text
    • http://karlsbach.de/userfiles/files/metifimepomog.pdfIn PDF document text
    • https://agrando.cz/files/file/japafafuje.pdfIn PDF document text
    • https://www.prshots.com/ckfinder/userfiles/files/62540262655.pdfIn PDF document text
    • 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_off0000db0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB0D 17496 bytes
SHA-256: 7c822e52aafd9cc9e575acb1f5d13d8f6d024b850b0a810741a11945bb076d2c
font_01_sfnt_off000108eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108EB 10504 bytes
SHA-256: 7827c9bba13cb58b89b66e5ace9f7e5ea84693b259952115352891409c4693c7
font_02_sfnt_off000120d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1