Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4d40e82c46b4d3d…

MALICIOUS

PDF

71.3 KB Created: 2021-09-24 23:09:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9ee5f2f86fa0f19b0061e8a2391fbb29 SHA-1: 01e7b0020692502691e02259998e662d792ff671 SHA-256: f4d40e82c46b4d3db1e18436e6f0d40f7153a32aa7cf27a6144e4d9f9740bad8
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of a phishing or trojan distribution. It contains numerous links to external PDF files hosted on various domains, many of which are flagged as disposable hosting or link farms. The presence of these links suggests an attempt to redirect users to download further malicious content or engage in phishing activities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://envigest.cz/upload/file/lopuruzixoborawateti.pdf In PDF document text
    • http://camonetinternational.com/files/file/kanevubukofosapufatujit.pdfIn PDF document text
    • http://hoangduy.vn/vn/files/61001936091.pdfIn PDF document text
    • http://sklenicky-obchod.cz/web/admin/fckeditor/userfiles/file/tukukofovuniruzilames.pdfIn PDF document text
    • http://brixtontaxi.com/survey/userfiles/files/20758493610.pdfIn PDF document text
    • http://budoprojekt.eu/obrazy/file/72887181616.pdfIn PDF document text
    • https://rajakeempat.com/contents/files/sojufem.pdfIn PDF document text
    • http://krr-nfe.com/suratnfe/UserFiles/File/redotub.pdfIn PDF document text
    • http://hiroi-es.info/yamituki-n/uploads/files/72316312247.pdfIn PDF document text
    • https://wittnebel.dk/file/3564576801.pdfIn PDF document text
    • http://ks4073.com/file_media/file_image/file/77608078043.pdfIn PDF document text
    • http://ferien-in-zahren.de/images/file/mifanugopuxezunun.pdfIn PDF document text
    • http://crocepadrekolbe.it/userfiles/files/1124634327.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16144ed84a4283---nujezivudexipev.pdfIn PDF document text
    • https://khmernative-rice.com/userfiles/file/80196620962.pdfIn PDF document text
    • http://traslochimontalto.it/userfiles/files/78581385541.pdfIn PDF document text
    • http://muntepa.com/userfiles/files/58952201967.pdfIn PDF document text
    • http://happyland-nsk.net/ckfinder/userfiles/files/wusavejok.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/161312d8db2d21---pewapuz.pdfIn PDF document text
    • http://ambulatorioveterinariosantanna.eu/userfiles/files/79171693712.pdfIn PDF document text
    • https://sunrisemotelbellevue.com/nbloom/fckuploads/file/xigogesosu.pdfIn PDF document text
    • https://rodolphe-blanchet.fr/Rodolphe/fckeditor/file/xelidukanudevodumuwubi.pdfIn PDF document text
    • http://gattoneva.pl/pages/userfiles/file/58490221896.pdfIn PDF document text
    • http://confidenzacsapagy.hu/upload/41959788428.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=download+naruto+shippuden+ultimate+ninja+storm+4+mod+apkPDF 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_off0000b10e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB10E 17236 bytes
SHA-256: b4974b461c02777544514d23235cc528642a8aa0c18f8c57974608e872a9bcaa
font_01_sfnt_off0000dd41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD41 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF558 11144 bytes
SHA-256: 143ea43e3d03bd55109600049f2db8263caa41b307ee964a7a40fda03c4d08bf