Malicious PDF — malware analysis report

Static analysis result for SHA-256 ffd76ca9728fe3ab…

MALICIOUS

PDF

80.8 KB Created: 2021-09-21 04:13:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 8afd89a012ec367ffc24c2c12f2acf13 SHA-1: c451e5699c44b895e226e6dead900784e7a0685b SHA-256: ffd76ca9728fe3ab03d24221494ad6a2320cc259e0d13468202576b9ed649fd1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the URL 'https://smidgel.ru/uplcv?utm_term=download+ms+office+2019+with+key' indicate a phishing attempt to trick users into downloading software. ClamAV detection and ML classification confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 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://smidgel.ru/uplcv?utm_term=download+ms+office+2019+with+key PDF link annotation
    • https://santa.my/images/users/00000000/files/70061138670.pdfIn PDF document text
    • http://ndt-ultratech.com/files/70230043970.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/jurumazodusetu.pdfIn PDF document text
    • http://puisan.ru/uploads/file/47665872377.pdfIn PDF document text
    • https://ceylanotel.com/firma/files/974874288.pdfIn PDF document text
    • http://teplo76.ru/uploads/file/mobizeditageva.pdfIn PDF document text
    • http://101balkon.ru/upload/files/81966009979.pdfIn PDF document text
    • https://namratalakhotia.com/userfiles/files/nubolixuzowilanak.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b395547217---66875640747.pdfIn PDF document text
    • https://dazhonghua1688.com/ckfinder/userfiles/files/51399619679.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140737294c36---kafodorevulukag.pdfIn PDF document text
    • http://grappin-annat-como.com/userfiles/grappin-annat-como.com/file/42997221677.pdfIn PDF document text
    • https://tpk-m.ru/files/file/dojekivedegaw.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148f70246a01---zagagidogetovaruj.pdfIn PDF document text
    • http://exim5.hu/_user/file/kijil.pdfIn PDF document text
    • https://alusol-kw.com/ckfinder/userfiles/files/44582014625.pdfIn PDF document text
    • http://it-hair.com/userfiles/sejufipugu.pdfIn PDF document text
    • https://davnosti.ru/upload/60723232421.pdfIn PDF document text
    • https://kamarkosong.com/contents/files/xoposomubevi.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613100b1094e2---ragimid.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_off0000d53a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53A 11396 bytes
SHA-256: 32921ebc0502e7845b16eb794a9495a23c3a625669ae627358b52981fa251e51
font_01_sfnt_off0000f01b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF01B 17480 bytes
SHA-256: bf225e9f6f15eb97633d878677cdd0afacc8e436c5bb0cbbb657a0ca295c4af1
font_02_sfnt_off00011da0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DA0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1