Malicious PDF — malware analysis report

Static analysis result for SHA-256 ed37f2d73fc15a7e…

MALICIOUS

PDF

74.0 KB Created: 2021-09-11 17:57:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a729c741e9a04d3fe90e9f709243585b SHA-1: 12ad85ae9421f378e7878dfd968b9dca691dde50 SHA-256: ed37f2d73fc15a7e2473293cded7bb47e8a279b0f4e831eb4b3acceb7ead75cb
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It presents a fake CAPTCHA, a common lure to trick users into executing further malicious actions or downloading additional payloads. The document contains numerous embedded URLs, many of which point to potentially malicious PDF files, suggesting a phishing or malware distribution campaign.

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
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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://khachsanmyngoc.com/upload/files/40569047683.pdf In PDF document text
    • http://rdmsrl.it/userfiles/files/12587837328.pdfIn PDF document text
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612f43a8eafbc---51780022078.pdfIn PDF document text
    • http://kientrucsangtrong.com/plus/files/52217890267.pdfIn PDF document text
    • http://yonseri.org/userfiles/files/jafajojek.pdfIn PDF document text
    • https://cbdc.co/uploads/ckfinder/userfiles/files/67157408926.pdfIn PDF document text
    • http://zamgph.com/FCKeditor/editor/filemanager/connectors/php/uploads/file/061526456462.pdfIn PDF document text
    • http://kidzcastleschool.com/singhania/downloads/file/wajoxonomazaberiguni.pdfIn PDF document text
    • http://www.specemc.ru/upload/files/48337206032.pdfIn PDF document text
    • http://hoteldarim.ir/basefile/hoteldarimir/files/jofelu.pdfIn PDF document text
    • http://chizclean.ru/files/fck/file/67103503845.pdfIn PDF document text
    • http://whatcanidoforyou.eu/publish/file/lamurekoposodiwozumisik.pdfIn PDF document text
    • https://rwd1.thadv.com/upload/files/vetonobilinotam.pdfIn PDF document text
    • http://alconsprom.ru/ckfinder/userfiles/files/supapakedenaxunujurexa.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/0c6f5c5d8c4cd6dc065b92015d04113a/93212973718.pdfIn PDF document text
    • http://pet.nfe.go.th/m_site/ckfinder/userfiles/files/71835392265.pdfIn PDF document text
    • http://siddharpeedam.org/userfiles/file/In PDF document text
    • http://qualityroofinnandsuites.com/nbloom/fckuploads/file/21834034362.pdfIn PDF document text
    • https://confidence-ist.com/ckfinder/userfiles/files/jobejasatalovowekapup.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/46240619249.pdfIn PDF document text
    • http://kargo-box.com/uploads/files/85121574405.pdfIn PDF document text
    • http://bpsstudio.hu/uploads/wifesuwalazisewiwite.pdfIn PDF document text
    • http://hatdesechia.com/storage/ckfinder/files/warimadovage.pdfIn PDF document text
    • https://epgeptech.hu/ckfinder/userfiles/files/60704569061.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=i+ve+forgotten+my+android+passwordPDF 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_off0000bcb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCB3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d4ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4CA 11012 bytes
SHA-256: bbfa5b7f05c5c382dd6fb2f0416e866d9553fb47203937c3312960f3ccee1638
font_02_sfnt_off0000ee43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE43 17360 bytes
SHA-256: 25d310c83624b1f45a1ad14dd87d0c17f817cbf6d1885b9d6f64eb030795382b