Malicious PDF — malware analysis report

Static analysis result for SHA-256 18955d5c256d042d…

MALICIOUS

PDF

80.0 KB Created: 2021-09-19 12:57:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5c11c486e868affef2c15bcf94f0b8de SHA-1: 3604d7f09d9af795ae824ef936f9b0ded4a20308 SHA-256: 18955d5c256d042d0b20e8e26a6325d3e6dbbba6ccde96f87822b8bf92bee81d
156 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to websites hosted on compromised CMS platforms or disposable hosting. This behavior is indicative of a link farm designed to manipulate search engine rankings or distribute malicious content. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://tidaksusah.com/contents/files/6088815112.pdf In PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/c084193519d8a55212bf9635d95cc24d/52362388795.pdfIn PDF document text
    • https://bandotrading.it/uploads/file/jopudemupaxemewixag.pdfIn PDF document text
    • http://studioingegneriavaragnolo.com/userfiles/files/vuwiginilolebuvijoramar.pdfIn PDF document text
    • http://spain-ex.com/images/blog/file/74315015623.pdfIn PDF document text
    • https://rewaqousha.net/userfiles/files/86831390598.pdfIn PDF document text
    • http://textstricker.de/benutzerdateien/1360344740.pdfIn PDF document text
    • http://www.valathors.com/ckfinder/userfiles/files/21105775772.pdfIn PDF document text
    • http://we-women.de/default/files/uploads/file/bonapidu.pdfIn PDF document text
    • http://chinasoftcore.com/userfiles/file///54416415547.pdfIn PDF document text
    • http://ottomaniantextile.com/userfiles/file/gafopijeweti.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/kuniperonatiwosa.pdfIn PDF document text
    • http://laserinnsbruck.com/static/pivomikower.pdfIn PDF document text
    • http://skupka23.ru/upload/m/85902333703.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/7d400e7dad6e7839cd91c1da8b64e15c/toraxuposusomepekux.pdfIn PDF document text
    • https://www.chablis-gautherin.com/ckfinder/userfiles/files/towabanajijuzelejilawam.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/a26dadb39d7a7faccd45b9f6a0ccbf63/wezidumizowisutosojojowin.pdfIn PDF document text
    • http://inbiosa.eu/static/cfiles/files/vanozaxedixineleliluxiw.pdfIn PDF document text
    • https://hazeloyun.com/calisma2/files/uploads/lamutezexezurogimo.pdfIn PDF document text
    • http://thietkewebsite.btccorp.vn/uploads/files/bobepomapup.pdfIn PDF document text
    • http://xingzhongjing.com/userfiles/file/20210902180952_1842369365.pdfIn PDF document text
    • http://n2nnetworks.com/files/others/xavororudivotaripozi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=videoshop+pro+apk+downloadPDF link annotation
    • http://tes-sys.com/uploads/ckfinder/files/20210912/16314031369609.pdfIn PDF document text
    • 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_off0000d4dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4DC 17996 bytes
SHA-256: a8242ee70478524a9ac868d56100ebb5dab473324528b31739385458ed50b83a
font_01_sfnt_off000102c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011add.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ADD 10540 bytes
SHA-256: e13ae188e2b538fd30496bb3ad2763d4fa810078414c5ec7e992fc7ecbc7a8b3