Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbdd9f33cdb5a83a…

MALICIOUS

PDF

83.7 KB Created: 2021-09-14 09:04:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4fb00e7a354761609c26ce58c3ca0369 SHA-1: fb53c78786c8d38d89ef920c6017b87ebd97f0d9 SHA-256: dbdd9f33cdb5a83a8ba68ce6dcc4b4fd8911795b94e734884177989e47fcedd3
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm. The PDF contains numerous external URLs, some pointing to compromised CMS upload directories, suggesting an attempt to lure users to malicious sites. The presence of a link farm and compromised hosting points towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://dayuntang.com/assets/uploads/ckedit/files/20210903002259.pdf In PDF document text
    • http://tetrafluoro.com/upload/files/jalivizilo.pdfIn PDF document text
    • http://shangrilatheshow.com/ckfinder/userfiles/files/newub.pdfIn PDF document text
    • http://oxigensupplies.com/shipinc/userfiles/files/povasukimodag.pdfIn PDF document text
    • http://www.syrahresources.com.au/application/third_party/ckfinder/userfiles/files/34605839936.pdfIn PDF document text
    • http://szjwwj.com/userfiles/file///fidosirupabigozexitufa.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/kiwemixunulaliruwupo.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/732e601357fe22b42c4cb572adb04a00/vavepazopobisifutumefove.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021091320335859.pdfIn PDF document text
    • http://888chji.com/userfiles/files/duzogilujagefazunuxikiwa.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612eaac72a1f5---zodezidadafozenuromireri.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-12/20210912052424481831.pdfIn PDF document text
    • http://terezszilvia.com/images/uploaded/file/63826973326.pdfIn PDF document text
    • http://cuboni.com/uploadfile/hong202109140704125716.pdfIn PDF document text
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/ae175ac9c315d2426ffbafceb3b17c35/gameruvesesabitimolofi.pdfIn PDF document text
    • http://istanbulballoons.com/ckfinder/userfiles/files/susopilususur.pdfIn PDF document text
    • http://js-space.de/userfiles/file/getokibirejifosuxabedal.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1612f170a7706a---55764487000.pdfIn PDF document text
    • http://citra.cl/userfiles/file/42160615603.pdfIn PDF document text
    • http://cuoredicane.it/userfiles/files/lerifisesexobexuredakuz.pdfIn PDF document text
    • https://trisyscom.com/userfiles/file/mufawepowu.pdfIn PDF document text
    • http://sevennews.com.br/ckfinder/userfiles/files/jojatekari.pdfIn PDF document text
    • http://food-cloud.com/home/food-cloud/www/site/site/data/files/39068631.pdfIn PDF document text
    • http://mictrogiang.com/userfiles/files/fusazawiwodadukewidib.pdfIn PDF document text
    • http://bluebirdcanada.com/FileData/ckfinder/files/20210906_26DA659122065C55.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+format+moto+g6PDF 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_off0000e235.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE235 18500 bytes
SHA-256: 048a80e4b86426ab0454e9a949775375f7beab4da0e784a8eb7c33dba51eb3e5
font_01_sfnt_off000111db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000129f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129F2 10260 bytes
SHA-256: 7ca99ef3b841101105722bced7ea06a73d5808b905f48385cae608437a7740b2