Malicious PDF — malware analysis report

Static analysis result for SHA-256 8983fc8288b02942…

MALICIOUS

PDF

79.2 KB Created: 2021-09-13 20:52:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 321605b544c7fee5d5b8c372af90cefa SHA-1: 44c9bc6ab31faadb28f6ee4bc31f701f5e1a4c88 SHA-256: 8983fc8288b0294258c0d93cfdf3dc56fb74f7a4ba64d27916b901d33aed2e1e
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised CMS upload directories, indicating it's designed to lead users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a link farm used to distribute further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613f40750f1ed---gomex.pdf In PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/8dcc036253776409b48bb74bf44adc89/kaxafiganakexu.pdfIn PDF document text
    • https://2winit.com/Files/files/nimog.pdfIn PDF document text
    • http://www.psychophonie-tarbes.com/ckfinder/userfiles/files/wowatekajesonisirekape.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/161323a1f44c5d---gibuba.pdfIn PDF document text
    • http://kfgame.snailgame.ru/upload/files/20210911224549.pdfIn PDF document text
    • https://dimensionshoppe.com/alpha/ckfinder/userfiles/files/darawelenipinezazar.pdfIn PDF document text
    • https://giant-nano.com/app/webroot/userfiles/files/voxowupetafapux.pdfIn PDF document text
    • http://hcvitamin.com/webroot/img/files/jagumimifewejazadepo.pdfIn PDF document text
    • http://cavusofis.com/images_upload/files/28578830153.pdfIn PDF document text
    • https://micro-logic.ro/images/uploaded/file/gifonosisolusukopotibenir.pdfIn PDF document text
    • https://sunridgecorp.com/uploads/files/202109081936354273.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/monipagufedulotevib.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/51675850552.pdfIn PDF document text
    • https://ocw.tw/uploads/files/37649305633.pdfIn PDF document text
    • http://vssteel1999.com/ckeditor/userfiles/files/silazuladiwidura.pdfIn PDF document text
    • https://uzunlarpeynir.com/dursun/upload/files/79844272864.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210905085838702.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/kanawow.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/zapubepotosegazavenojapo.pdfIn PDF document text
    • http://rszm88.com/upfolder/e/files/20210904120146.pdfIn PDF document text
    • http://www.moyekolodin.com/files/80875867913.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/nezat.pdfIn PDF document text
    • https://medgal.pl/admin/ckfinder/userfiles/files/76578141437.pdfIn PDF document text
    • http://auburn-properties.com/userfiles/files/moxajokefutotodozowewese.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=kamasutra+positions+book+pdfPDF 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_off0000d1b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1B7 17496 bytes
SHA-256: d8f4e944cb4239a02f98b90011276835777c7340f31a23228162a29f918eba76
font_01_sfnt_off0000fde9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDE9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011600.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11600 10804 bytes
SHA-256: 23d8537336e7e28c67170ec939167acec721bfcf01d2bff6af59c37a7f01a401