Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d8ad0e549c038a5…

MALICIOUS

PDF

70.4 KB Created: 2021-09-24 22:00:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f5edfd6506a78400723816935a67af81 SHA-1: 03c8b9e838f1de86a6ed4c4a21a80c82a027ae63 SHA-256: 4d8ad0e549c038a574fddafa4aaea53237fa718c4e373a9f2d0170b7469c50af
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to lure users to external sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The presence of multiple PDF link farm heuristics reinforces the conclusion that this document's primary purpose is to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://potlista.com/file/files/31699241067.pdf
    • http://arqing.es/ckfinder/userfiles/files/tibijiwa.pdf
    • http://take114.kr/FileData/ckfinder/files/20210910_F1DFAF9203F0A8CD.pdf
    • http://apmnir.ro/fckfiles/file/12454876115.pdf
    • http://koreabulk.net/userData/board/file/6053970445.pdf
    • http://bezagsecurity.cz/userfiles/jubuvijo.pdf
    • http://homeshopeez.com/uploaded_files/userfiles/files/94298019583.pdf
    • https://suprizpin.com/calisma2/files/uploads/puvasosudukopudijipabaz.pdf
    • https://bosgo.mn/uploads/files/67219021992.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16142ae3a34eb8---patuxi.pdf
    • https://capital-publishing.com/ckfinder/userfiles/files/53065326472.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/16136c903019aa---10929521116.pdf
    • https://terminarz.online/kosmetyczka/krakow/files/xixumunowuvebi.pdf
    • http://riph.pl/userfiles/file/61926295581.pdf
    • http://www.omt.ntou.edu.tw/ckfinder/userfiles/files/repowegozo.pdf
    • http://jmvlpslimited.com/ci/userfiles/files/xopumunefolubimejoli.pdf
    • https://btegypt.com/file/5883148834.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/54i5ctc5a8106ud688vkb14s1s/lotogenukalatijitu.pdf
    • https://miguktour.com/FileData/ckfinder/files/20210906_67940212F3A7378D.pdf
    • http://hzzxtl.com/UploadFile/file/20210908011004612.pdf
    • http://work4shop.cz/userfiles/file/musurusabajimopusif.pdf
    • https://faresaldabbous.com/uploads/files/wituset.pdf
    • http://kiuanai.com/userfiles/file/72259817955.pdf
    • https://baust.edu.bd/app/webroot/ckfinder/userfiles/files/bufolikuvopen.pdf
    • http://tamtamphat.com/upload/files/lowowitafa.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=madden+nfl+21+mobile+download
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b45c.bin
b08c9399006a354160b5dee4e744b8d7b00229ea19d385bbb4c2d0b9cbebdf97
pdf-font-stream PDF embedded font (sfnt) at offset 0xB45C 15604 bytes
font_01_sfnt_off0000dbe7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBE7 16792 bytes
font_02_sfnt_off0000f3fe.bin
0cd5b8b2f4790a2de3c2a1aa741d3e8d09bf17c04df315b1a39bdf8776ffe2b2
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3FE 10540 bytes