Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3b628877ac6642d…

MALICIOUS

PDF

78.6 KB Created: 2021-09-13 17:57:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 1eafed3db7e47995ebeed3f938c3a49a SHA-1: 56da4cf1d5c7fd8ff5f14460772a48732e9aa07a SHA-256: d3b628877ac6642db61ba27353f7a34bf3cd248f9377e3531f8ba0440805875b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which are structured as link farms, suggesting an attempt to obscure malicious intent. One heuristic specifically identifies a link farm on disposable hosting with a UTM term redirector, pointing towards a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate maliciousness, with ClamAV identifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://automsystem.com/UploadFile/file/20210910143413662.pdf In PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/besegusorafilozitopuz.pdfIn PDF document text
    • http://stickers-moins-cher.com/userfiles/stickers-moins-cher.com/file/35365066024.pdfIn PDF document text
    • https://salondumariagededijon.com/userfiles/file/34696319247.pdfIn PDF document text
    • https://rheinfurth.de/userfiles/file/mivurenagukabegumure.pdfIn PDF document text
    • http://strahyi.ru/images/file/binikikajukajudepupajewi.pdfIn PDF document text
    • https://pilot-nav.socksnbows.com/ckfinder/userfiles/files/55280208791.pdfIn PDF document text
    • https://gornjastubica.hr/files/8502750473.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/b71db2a7d00192a1bbcf149b835e33cf/14195708266.pdfIn PDF document text
    • http://hoadon-dientu.net/images/files/37654750535.pdfIn PDF document text
    • http://vitalchurchesinstitute.com/files/file/baxazuvanozozirum.pdfIn PDF document text
    • http://sabaispa.net/userfiles/file/burusuvigijaw.pdfIn PDF document text
    • http://auto-rad.pl/userfiles/file/vaxopesogumepuwejobup.pdfIn PDF document text
    • http://unibox.lv/files/text/gijemewepezuzeduzadi.pdfIn PDF document text
    • https://cvzona.lt/resources/img/files/85540751955.pdfIn PDF document text
    • http://flexinform.com/hirlevel/file/57732362843.pdfIn PDF document text
    • http://aesg2edcv.handylover.com/upload/files/muluwen.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021090819452142.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136a5319aa72---99214837368.pdfIn PDF document text
    • http://tourhong.com/FileData/ckfinder/files/20210912_DAF1C777A9FB94A2.pdfIn PDF document text
    • https://przyklejki.pl/userfiles/bejajujigokinusutuzife.pdfIn PDF document text
    • https://virtualpulse.eu/UserFiles/file/dusazebomulumodemenam.pdfIn PDF document text
    • https://rumusjitu.com/contents/files/fuwoxizezibiwefedoxofex.pdfIn PDF document text
    • https://usssecuritate.ro/userfiles/file/rusawatusuposotilubi.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/kimurelanofalakixiwamawuw.pdfIn PDF document text
    • http://matras-devison.com/upload/file/pomifefawe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=download+gta+5+beta+versionPDF 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_off0000cdfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDFC 10852 bytes
SHA-256: 839cd9f1d32026e23f60172cc8545dd5e4203a5c0cf3e4bf8d498d1c0b017321
font_01_sfnt_off0000e715.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE715 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ff27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF27 17492 bytes
SHA-256: aedd5bf1994d6698309b3f4a5d80ba2bf5ed890be42a7e4fdf3d8b7fe613286a