Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4fd0fecbb33b38f…

MALICIOUS

PDF

75.2 KB Created: 2021-09-18 03:07:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 08072686658e5f099122939a3e986c33 SHA-1: 03c9bf9c6a82342978b4001c7bc1970d99333f64 SHA-256: b4fd0fecbb33b38f3628440f63c0db3e0304f3a27abdfe795a87751ca852100a
156 Risk Score

Malware Insights

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

The file is a PDF containing a large number of external links, many of which point to potentially compromised or disposable domains. Heuristics indicate this is a link farm, likely used for SEO poisoning or to lure users to malicious content. ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious intent, possibly related to phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://gccde.com/downloads/blog/geust/files/tewodasax.pdf In PDF document text
    • https://smshealthcareservices.com/ckfinder/userfiles/files/dolosulekados.pdfIn PDF document text
    • http://meditopthailand.com/file/wuvuribexatozixaboroxelon.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/hpb1p9bi55vg17s5npa71a7krc/rezedefaxanupusalunugo.pdfIn PDF document text
    • http://lpxs168.com/filespath/files/20210907073029.pdfIn PDF document text
    • http://mtreurope.com/ckfinder/userfiles/files/kaxezarodog.pdfIn PDF document text
    • http://suurelepa.ee/data/file/83785012527.pdfIn PDF document text
    • http://wolfpackbasketballacademy.com/content_docs/12194059615.pdfIn PDF document text
    • http://hoachattn.com/image/files/warebedobewarisegivujipip.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/1484071301.pdfIn PDF document text
    • https://chaletsuenodesol.de/files/rifebejikikepubov.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16134091fe9b46---5891827764.pdfIn PDF document text
    • http://jplus-ag.com/upload/files/BodyFile__6142CA3CB26FC.pdfIn PDF document text
    • https://tideandtigers.com/ckfinder/userfiles/files/92520240431.pdfIn PDF document text
    • https://angelsforwarriors.org/userfiles/files/kitikopujodima.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/xubowozogor.pdfIn PDF document text
    • http://newtarrytowndeli.com/uploads/files/10689567903.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/16142e0d206d06---zokakowiradav.pdfIn PDF document text
    • https://pensiuneaselina.ro/userfiles/file/38983530478.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/64824244556.pdfIn PDF document text
    • https://vasutaszeneiskola.hu/ckfinder/userfiles/files/50292178845.pdfIn PDF document text
    • http://remont-etalon.ru/upload/files/bopilekodokufuvan.pdfIn PDF document text
    • http://sarkanyhajo.hu/files/file/buxebifepusamugeromono.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=the+bible+fraud+tony+bushby+pdfPDF link annotation
    • 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_off0000c193.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC193 10912 bytes
SHA-256: 15d3d6cad862b50a1f0e64cbbe994137607b3de05823badd6c664c75f79ffbc4
font_01_sfnt_off0000da89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA89 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f29b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF29B 17144 bytes
SHA-256: 65523feac7adc6bd7cbfb499b6c95095f21a9ec4655145e5f6244892104286be