Malicious PDF — malware analysis report

Static analysis result for SHA-256 623130cb99409727…

MALICIOUS

PDF

88.3 KB Created: 2021-07-13 22:18:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: ed00a82f8da3112cc830790bfe1029cf SHA-1: 41911bc0538efc4204ec865d02421b8a816fd199 SHA-256: 623130cb9940972761e137b74e66b6a61bf9ba895a9555fa2cdf6050296adad2
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised WordPress sites and disposable hosting. The document body is unreadable, but the presence of numerous external links suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://1877painters.com/FCKeditor/file/fijijevuneguw.pdf In PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/1cfcc11efad0dd5eb7e87f1fa191a1dc/wuxitadomo.pdfIn PDF document text
    • http://hifimarkt.org/kunden/kronhardt/ckfinder/userfiles/files/21790249123.pdfIn PDF document text
    • http://rainbowcaterers.in/userfiles/file/27383046729.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/itqbbbellg189qpk8odvvuphh9/xikodaxisokegag.pdfIn PDF document text
    • http://southwest62.com/clients/6/66/666176aa584decdbf8d0f1e9213c5ee1/File/lajokawitaj.pdfIn PDF document text
    • http://studioriggio.it/userfiles/files/52779923276.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160adc81e9656d---24726339420.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/oip7la3490g89tg9h882k2u80r/bavopufefiregiv.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/25101457895.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/dunojuvapetiker.pdfIn PDF document text
    • http://www.aadhar-interior.com/userfiles/file/kifasekalegiviruxafove.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0b71d33c6---dipasunetaropu.pdfIn PDF document text
    • http://charivne.info/images/file/53492258874.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160947416d3825---84810762924.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16083f7e804b3b---66328342409.pdfIn PDF document text
    • http://theatresaucinema.fr/uploads/file/75884468859.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/60606133771.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf0ba2973f2---rojediku.pdfIn PDF document text
    • http://activesolutionelectric.com/images/file/tapezosomajuroxunezutuf.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1608521b4a9b4e---wupama.pdfIn PDF document text
    • https://ikincielinmak.com/upload/ckfinder/files/94358637381.pdfIn PDF document text
    • http://bettynblue.com/upload/fck_img/20210522/file/27262459779.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=captive+bred+chinese+water+dragonsPDF 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_off0000f619.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF619 11068 bytes
SHA-256: 2cbdd2c8c4ebd0a0caafc7847db344c5fde80dad48b6de2df423326762f749d2
font_01_sfnt_off00010f8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F8B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001279d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1279D 16996 bytes
SHA-256: d2d1b93f945e640191e81cc80bb2cf562050919d630712165626b0d96fac8942