Malicious PDF — malware analysis report

Static analysis result for SHA-256 037a3d1fdaebeac2…

MALICIOUS

PDF

77.6 KB Created: 2021-09-15 09:11:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 145410e46d1a9111590e1d8c53b016a8 SHA-1: bd1e41d545e5d3f5e036fb7dd6c1e9f84d7f72b1 SHA-256: 037a3d1fdaebeac2a4e5195c06c2fcd424cf04248de2608fcb5a1163ee109e45
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a large number of external URLs, many hosted on compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or redirecting users to malicious content. The embedded JavaScript is a common technique for exploiting PDF vulnerabilities or initiating further malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 7

  • 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.
  • 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://wastran.ru/uplcv?utm_term=missing+system+image+android+studio PDF link annotation
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/ca0b62ce5a2171b1738064b255fa5f03/44268185485.pdfIn PDF document text
    • http://teplo76.ru/uploads/file/44420938050.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613bfc95d5b85---bogamubusaluzujawawumus.pdfIn PDF document text
    • https://kiofruits.com/admin/uploads/files/58911677218.pdfIn PDF document text
    • http://ibconsulting.it/userfiles/files/38756100743.pdfIn PDF document text
    • http://bellamy.tw/uploads/files/202109092312091596.pdfIn PDF document text
    • https://sintasyapi.com/img/userfiles/file/56261808258.pdfIn PDF document text
    • https://cpsguffanti.com/uploads/file/givajefapix.pdfIn PDF document text
    • https://omegaplus.bg/uploads/pages/files/nosakapev.pdfIn PDF document text
    • http://viviapalermo.com/userfiles/files/kugitepizawezeriru.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/0635493cd349197f4c9e153d19059459/sovoletu.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137d13fe6c4e---xubid.pdfIn PDF document text
    • https://happy-playground.gr/uploads/_uploads/files/rifofutosuwowafox.pdfIn PDF document text
    • http://asu78.ru/userfiles/file/sajulunavogukewomi.pdfIn PDF document text
    • https://eventaipei.com/upload/files/59483006816.pdfIn PDF document text
    • http://bachtungcompany.com/upload/files/jonafo.pdfIn PDF document text
    • http://pickup-ws.com/userfiles/files/15140904333.pdfIn PDF document text
    • http://ametansk.ru/uploads2/50577737190.pdfIn PDF document text
    • http://piannocreativo.com/js/new/fckeditor/userfiles/file/nobamorag.pdfIn PDF document text
    • http://bwc.lt/i/66918189986.pdfIn PDF document text
    • http://fernandopelosini.it/userfiles/files/vigopugowod.pdfIn PDF document text
    • https://cubic.is/userfiles/file/71619697019.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_off0000cc5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC5F 10752 bytes
SHA-256: ed393fb832390559c940bb066b5810a300b67d49def1712b051c07ccb8c098a3
font_01_sfnt_off0000e4e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4E8 16972 bytes
SHA-256: bf1cf2cc7d8f1bf75c2bf393cd3de7985711c629630c8a601cb4375e76967f56
font_02_sfnt_off00011159.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11159 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1