Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4771dda5b58ced0…

MALICIOUS

PDF

76.4 KB Created: 2021-08-20 18:45:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 29dd5dd29eff3e21e64b846fbc46a45f SHA-1: 5639834fbc4acd5b588cec758a9b3c13c07df30d SHA-256: b4771dda5b58ced073b68d7322542b447339c49bf564218422c057ca142addb1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to websites hosted on compromised Content Management Systems (CMS) or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or SEO spam. Although no scripts were explicitly extracted, the PDF structure and URL patterns suggest it's designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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 farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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=glencoe+algebra+1+answers+chapter+5 PDF link annotation
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/b536d39e4656307224c69b9ea1a36d2a/larewafinuduju.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/16100c1ecc561a---gajudawofam.pdfIn PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/0ba2d2fa9175dcb1d96189fc896a2e80/95766654842.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad3067e600---jejizafekupogolusafut.pdfIn PDF document text
    • http://hurtglass.pl/upload/file/4694022443.pdfIn PDF document text
    • http://huntland.hu/upload/file/samuzatimazonawij.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084f0fa5e365---giwigowagajowelajavajapeg.pdfIn PDF document text
    • https://zzhqhi.com/d/files/xupelaru.pdfIn PDF document text
    • https://crossfitbeeshark.ro/app/webroot/files/userfiles/files/32786627729.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609cbd87b763c---76864204061.pdfIn PDF document text
    • https://rubin2000-distribuitorshop.ro/userfiles/file/zutiralife.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/84dd4e6b7b55e8da8c686d2a328aa2bd/jukeler.pdfIn PDF document text
    • http://sinners-party.de/media/file/60140993543.pdfIn PDF document text
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a6ab3d94c7b---nakoxur.pdfIn PDF document text
    • https://www.autodepotperformancegroup.ca/wp-content/plugins/super-forms/uploads/php/files/n2k8pnj41nfkmguims78buj010/nolofu.pdfIn PDF document text
    • http://vector-luczak.pl/new/fck_user_files/file/durixakoxur.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607751bb95b78---nobedosifobejofigudisezot.pdfIn PDF document text
    • https://www.weboonline.com/ckfinder/userfiles/files/58200267110.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a9312d331a9---62913078025.pdfIn PDF document text
    • http://wowbond.com/upload/Fckeditor/file/23722268224.pdfIn PDF document text
    • https://panificioilcavaliere.it/userfiles/files/bonapubumusefo.pdfIn PDF document text
    • http://suaups.net/userfiles/file/91128789390.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afda2c35d9a---11176677548.pdfIn PDF document text
    • https://mayxaydungthienlong.com/uploads/files/files/30153491300.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/e6915b04ccb01b14872f698731c57b5e/48500286453.pdfIn PDF document text
    • http://pro.ovh.net/~tribuene/images/banque/file/ledukik.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_off0000c2ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000daff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAFF 18632 bytes
SHA-256: a167945438a66e0821b7dfb4d713500f7ebaedcff3a229f943817876d66bbf21
font_02_sfnt_off000109a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109A3 11012 bytes
SHA-256: 0b5d60926447b9e1cab674b6b5c3b4affed01104b80b85088138b55738bb6c98