Malicious PDF — malware analysis report

Static analysis result for SHA-256 87b6724afc8c9f24…

MALICIOUS

PDF

86.6 KB Created: 2021-09-18 11:26:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 98e44367d5c50905fba93897a892c242 SHA-1: ffd87e3869772d9a0523f964a6feaef082b8d03a SHA-256: 87b6724afc8c9f24ba7d225179f97f1647f1af65f5e816ce1596048eb69ec81d
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS upload directories or disposable hosting, suggesting a phishing or malware distribution scheme. The presence of embedded JavaScript indicates an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pixomot.ru/uplcv?utm_term=fastboot+rom+for+redmi+k20+pro PDF link annotation
    • https://sarenpinler.com/calisma2/files/uploads/56963093593.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613cfe1e88151---sufafut.pdfIn PDF document text
    • https://verredistri.fr/xmedia/file/vezulasonoti.pdfIn PDF document text
    • http://www.clc-engineering.com/siteuploads/editorimg/file/setosejigovibomavirada.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/futomodofovoj.pdfIn PDF document text
    • http://79.170.40.182/boothtastic.com/wp-content/plugins/formcraft/file-upload/server/content/files/161394c7429ffe---virufu.pdfPDF link annotation
    • http://dongbanja.com/userData/ebizro_board/file/36748886383.pdfIn PDF document text
    • http://daisin1977.com/js/upload/files/14722366411.pdfIn PDF document text
    • http://avatars.ru/userfiles/file/pinitimedizemux.pdfIn PDF document text
    • http://getwealthythisyear.com/ckfinder/userfiles/files/71693440733.pdfIn PDF document text
    • https://ceccargiurgiu.ro/userfiles/file/92947813624.pdfIn PDF document text
    • https://kohphanganhotelandtour.com/userfiles/file/matesefulajolafimebu.pdfIn PDF document text
    • http://atreve.eu/ubezpiecz/obrazy/file/foruzemuvokojufapubutemu.pdfIn PDF document text
    • http://tasteofruraleurope.eu/upload/File/83310236527.pdfIn PDF document text
    • https://giant-nano.com/app/webroot/userfiles/files/pamojegizewibakag.pdfIn PDF document text
    • http://bamboomfi.com/htdocs/cljr/data/files/fapukixevurixubozogibufut.pdfIn PDF document text
    • http://debrecen.varosom.hu/userfiles/files/bisosujixogomom.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16134fd4c0fbdb---bizagejekelobexuwom.pdfIn PDF document text
    • https://matao.ro/app/webroot/files/userfiles/files/gonupijare.pdfIn PDF document text
    • https://servicepapik.ro/files/57326995764.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/e6956f7fb38deb5cbe20cb4fe0a4e5d1/88391359392.pdfIn PDF document text
    • http://hvpeds.com/upload/contents/file/lesemepenu.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/polijab.pdfIn PDF document text
    • https://sooryasales.com/uploads/file/53779671943.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_off0000eb23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB23 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001033a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1033A 10960 bytes
SHA-256: 3fbbf0adef0f8d2e22c996498b2b0c074a84c1aeb1e0909552a38bfa1ed9f3eb
font_02_sfnt_off00011c83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C83 18508 bytes
SHA-256: b781c922863c778804f74a6c3b23e295690d785ba9e9ddd6aeaa840388f8e675