Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9a24f50e9383f0b…

MALICIOUS

PDF

82.5 KB Created: 2021-09-21 05:38:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9320277d9891ed1572493bf95e39b4ac SHA-1: e96e4c8ed84bb40ebcfa72d32e5dcd52760490bd SHA-256: a9a24f50e9383f0ba7a1ea9bcd73ef65a45052b0e2e75275c76cbdd5f5e1fc44
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm with numerous URLs pointing to potentially compromised websites, as indicated by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://pistant.ru/uplcv?utm_term=ouran+highschool+host+club+stream+online PDF link annotation
    • https://delaneyllc.cfonewsletter.com/ckfinder/userfiles/files/30936969517.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd432dd06e---pupotogidir.pdfIn PDF document text
    • http://ok-poland.com/userfiles/file/tixopomiwukekirur.pdfIn PDF document text
    • https://careerroots.net/ckfinder/userfiles/files/29196220986.pdfIn PDF document text
    • https://bunyaminerdemir.com/resimler/files/janopepunaz.pdfIn PDF document text
    • http://kaus21.com/userData/board/file/ribavujedekuposafeb.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1613bf2852efb2---kegizozedubesuvurarodobiv.pdfIn PDF document text
    • http://vinag7furniture.com/app/webroot/files/editor_upload/files/61649473113.pdfIn PDF document text
    • http://srividyaastrology.com/userfiles/file/17105530707.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/161455ee628093---71928172581.pdfIn PDF document text
    • http://puzynowska-kancelaria.com/userfiles/file/nenafaba.pdfIn PDF document text
    • https://www.supremecaravans.com.au/application/third_party/ckfinder/userfiles/files/puxunesujivifarewikis.pdfIn PDF document text
    • https://momsgardenfoods.com/ckfinder/userfiles/files/61504901660.pdfIn PDF document text
    • https://euforbiabulgaria.com/uploads/pages/files/kilenazuxifelawakilemuzim.pdfIn PDF document text
    • https://tonmathunglan.vn/upload/files/16402364517.pdfIn PDF document text
    • http://stefanourso.com/public/userfiles/file/dojesibez.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16141378bb768b---temusef.pdfIn PDF document text
    • http://kechengchem.com/upload/files/39437477711.pdfIn PDF document text
    • https://bursakaynak.net/userfiles/file/fadotobuda.pdfIn PDF document text
    • http://cappellastudio.it/userfiles/files/73348995121.pdfIn PDF document text
    • http://sibleyestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fuxomigujakitome.pdfIn PDF document text
    • https://virtrade.gr/userfiles_lybo/file/sidev.pdfIn PDF document text
    • http://dc-a0dcf319a153.breakthroughsport.com/userfiles/files/pafobuwiludibamote.pdfIn PDF document text
    • http://ssanadia.in/userfiles/file/23339055745.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_off0000d9ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9BA 10944 bytes
SHA-256: adb88d3d33351437eb2fced280bd67beafd54981dfa34032f280aea1ee7cef5a
font_01_sfnt_off0000f2e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010afb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AFB 18208 bytes
SHA-256: cc8457474b71e1bcaa094bbbe6662aca161634903a5c991e253559a559ec8f54