Malicious PDF — malware analysis report

Static analysis result for SHA-256 76b144e2658ef054…

MALICIOUS

PDF

70.4 KB Created: 2021-09-25 21:53:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 28c939dab8f6b4868d0551e35f498adb SHA-1: c63b9f76066f7b06b25c3b5e842df65e511897c8 SHA-256: 76b144e2658ef054eef688082f91109d68a34069a56deaf0abeaf9dbc1788bb1
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple external links, with one identified as a randomly generated URL likely leading to a malicious payload. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the PDF is structured as a link farm on disposable hosting, further suggesting malicious intent. ClamAV detection and ML classification confirm its malicious nature, likely serving as a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://sameiroeventos.pt/ficheiros/186941453.pdf In PDF document text
    • http://architettogherardi.eu/userfiles/files/68124931569.pdfIn PDF document text
    • http://edisonprivateschoolbeta.com/cote_dor_import/admin/ckfinder/userfiles/files/luxewiraki.pdfIn PDF document text
    • https://rsvforum.com/userfiles/file/96117369760.pdfIn PDF document text
    • http://sanarina-coaching.de/ckfinder/userfiles/files/kasotufakirisujejale.pdfIn PDF document text
    • http://haithuanphat.com/uploads/files/97629542974.pdfIn PDF document text
    • http://ros-grad.ru/fck_editor_files/files/22000430016.pdfIn PDF document text
    • http://klinok-saintp.ru/files/sifuvefixutiwizufoxu.pdfIn PDF document text
    • http://lucidarepavimentimarmogenovaealessandria.it/userfiles/files/mafekuwija.pdfIn PDF document text
    • https://weekendtripskolkata.com/userfiles/file/suzevegesupimugotubawano.pdfIn PDF document text
    • https://nodka.eu/ckeditor/ckfinder/userfiles/files/77324272983.pdfIn PDF document text
    • http://josepholszowka.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50948836810.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161482b769fe2b---38035595867.pdfIn PDF document text
    • http://vpsystem.com/files/fck/jevobibutalil.pdfIn PDF document text
    • http://elfast.ru/userfiles/file/13212718901.pdfIn PDF document text
    • http://kramor.bg/userfiles/file/fugimorefopatoxenepila.pdfIn PDF document text
    • http://highlevel.pl/userfiles/file/vojigibe.pdfIn PDF document text
    • http://robvancampen.nl/userfiles/file/xizavaxubaxixukufadela.pdfIn PDF document text
    • http://cnhhgj.com/upfiles/userfiles/file/33068539234.pdfIn PDF document text
    • http://bluebirdcanada.com/FileData/ckfinder/files/20210912_6C9B6C7A509FB2B8.pdfIn PDF document text
    • https://jmclimatizacionhvac.cl/images/subidas/file/pasudagaxupep.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16146357bac13f---7711294887.pdfIn PDF document text
    • http://cerritos.songhakbbq.com/uploads/files/fajozafifilosavorinop.pdfIn PDF document text
    • http://highendschmiede.de/highendfiles/file/45618168649.pdfIn PDF document text
    • http://italiangreyhound.pl/img1/userfiles/file/60199374750.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=the+sims+freeplay+cheats+unlimited+money+2021PDF 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_off0000b172.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB172 11356 bytes
SHA-256: 4d73ca848f6c688b9452139e6f6d2683f83049c6ba50cf1131bf91f27a7138dd
font_01_sfnt_off0000cc17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC17 15568 bytes
SHA-256: fa8f1b8222c49129ea5052627afb38be12912c1dc459c356812edd046546ced5
font_02_sfnt_off0000f3af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1