Malicious PDF — malware analysis report

Static analysis result for SHA-256 a69472ecedb4e8ec…

MALICIOUS

PDF

88.8 KB Created: 2021-10-12 12:32:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: acc4745d362c67d8ab1bb89f4c7c4b46 SHA-1: e6067316b14e73f17d76b060fb9c1f97c9123332 SHA-256: a69472ecedb4e8ec5a056806971f3002d6a2be7006369c5d22f4adb054e339ed
126 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it's a link farm on disposable hosting. The PDF contains numerous embedded URLs pointing to other PDF files, suggesting a tactic to inflate search engine rankings or distribute further malicious content. No scripts were extracted, but the overall structure and URL patterns are indicative of a phishing or SEO spam campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://olymp-kiev.com/temp/fckeditor/file/32221944188.pdf In PDF document text
    • https://interangkorcondominium.com/userfiles/file/telenumimedopoparu.pdfIn PDF document text
    • http://launensia.cz/ckfinder/userfiles/files/vedegowisolamone.pdfIn PDF document text
    • https://mauspro.net/upload/files/pasejinafabi.pdfIn PDF document text
    • https://futuresbuilder.net/dayafter/uploadimages/newsimages/file/25594391901.pdfIn PDF document text
    • https://multimetrics.com/ckfinder/userfiles/files/vowijajekarikimax.pdfIn PDF document text
    • https://eledigitalpr.it/allegati/file/67712629623.pdfIn PDF document text
    • http://vce34.ru/attachments/file/genagegopu.pdfIn PDF document text
    • http://paoladebenedetti.eu/userfiles/files/lebam.pdfIn PDF document text
    • http://edins.net/userData/ebizro_board/file/tagasosasuremiledu.pdfIn PDF document text
    • https://netiko.fr/img/Data/file/15568551637.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/29908117265.pdfIn PDF document text
    • http://skmsm.com/userData/board/file/sovasozokalelunava.pdfIn PDF document text
    • http://imhyuk.com/imhyukeditor/userfile/file/safuzojidim.pdfIn PDF document text
    • http://aktifimmo.lu/userfiles/files/kapewepupisobasidevopila.pdfIn PDF document text
    • http://koreanhotpot.com/uploads/files/pinixezufikurarugib.pdfIn PDF document text
    • http://s4l.vn/storage/ckfinder/files/32300114600.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021091321441163.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/fusemenesuxokiwi.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/nilufunanipikusev.pdfIn PDF document text
    • http://signauction.net/userfiles/file/visizem.pdfIn PDF document text
    • https://svingenieria.cl/userfiles/file/kufazilagupiwuxe.pdfIn PDF document text
    • http://fabtur.ru/upload/files/55872290439.pdfIn PDF document text
    • http://dieterheich.de/images/uploads/file/14999647058.pdfIn PDF document text
    • https://bda.ch/ckfinder/userfiles/files/refuvemurur.pdfIn PDF document text
    • https://veaodaibrahma.com/uploads/image/files/1652439660.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/2I9n2o-U8HI/uplcv?utm_term=blue+hair+quotesPDF 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_off0000f275.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF275 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010a8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A8C 10400 bytes
SHA-256: dca211b19bf5a405d5fa25f62cdeb74ebda4f3c70d05750f4c1fcf85bcbf6049
font_02_sfnt_off00012240.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12240 20292 bytes
SHA-256: d1cc7c1e544c5907db90964e1f61fdf984df6ead39dc5daeec2ec4402652e2ab