Malicious PDF — malware analysis report

Static analysis result for SHA-256 b34622f695445282…

MALICIOUS

PDF

81.4 KB Created: 2021-09-03 15:18:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2e474460f4c485aaa45f5f22db9ab448 SHA-1: fb907fbfe836cb9b701ae1d008fc7c4ea6033d56 SHA-256: b34622f695445282571dd1348eec25b95d68cd9087b388175bbda493ef78adea
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF acts as a link farm, directing users to compromised websites and potentially disposable hosting. The URLs extracted suggest a phishing or malware distribution campaign, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/4d40e48b2bdc9784e5720de3bd00e251/4414274080.pdf In PDF document text
    • http://konditsionery-reutov.ru/upload_picture/file/xagosowoxaretelunepepo.pdfIn PDF document text
    • https://casalindasbakery.com/ckfinder/userfiles/files/mewanomosolowalegixe.pdfIn PDF document text
    • http://www.css-jp.com/upfile/files/2021/07/28/suvezasibopirabuxut.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/nonadamidujosilabebu.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/remifojowekizupu.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/palakizomubawugawigagawir.pdfIn PDF document text
    • https://pima-alarms.rs/slicice/file/43526396242.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/rt2tknn6dhtkoute0radpg517a/xikoba.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/53120842855.pdfIn PDF document text
    • https://kltccompany.com/ckfinder/userfiles/files/80174181296.pdfIn PDF document text
    • http://stonebreaker.at/38779405051.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0eaea442f0---17028669649.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/893a234d1b206ce693fcb96f89238c2c/83195672933.pdfIn PDF document text
    • http://bienbao.org/uploads/files/suririsebowuxabaji.pdfIn PDF document text
    • http://poslovniimenik.net/firme_data/files/68717874836.pdfIn PDF document text
    • http://indagosrl.it/userfiles/files/tasuxodavevosotoxusasor.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/raliz.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/39e55f2f8ff6143ab94fcf1820c21336/rixojowemige.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/936f5e4ab81019d3e1cb3211ef7f8498/98936138281.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=manually+uninstall+office+2016+for+macPDF link annotation
    • http://zs.tom.ru/jsplugins/ckfinder/userfiles/files/mugeki.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_off0000d853.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD853 17608 bytes
SHA-256: 9d565ea55c4f369981f11c581ee68bfc32dd44539a388f5890a94d83e70a1b27
font_01_sfnt_off000105d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105D7 11164 bytes
SHA-256: def0bafe08e7182788ebef9510be041a2aa7b061447d69a38bbe10cbefa9ff32
font_02_sfnt_off0001201d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1201D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1