Malicious PDF — malware analysis report

Static analysis result for SHA-256 b26b839c6ea4f421…

MALICIOUS

PDF

69.2 KB Created: 2021-10-04 00:13:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: aafefe62c5f27f6878f1105061d1f861 SHA-1: 1998438088952a884cb21335eb4c77ad5f40be8b SHA-256: b26b839c6ea4f421986d405e8a2ec8fac4cf4235c7cf3ebb4b393362dc74e4fe
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier flagged it with high confidence. It contains embedded JavaScript and a large number of external URIs, many of which point to compromised WordPress upload directories or are part of a link farm on disposable hosting. These elements suggest the PDF is designed to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://oniceh.ru/uplcv?utm_term=football+bet+prediction+for+today PDF link annotation
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/00b0b5e14c57f85d3eb9c3516ed1eecb/61515399141.pdfIn PDF document text
    • https://hatinhjobs.com/upload/files/1935972263.pdfIn PDF document text
    • https://polymadeniyaglar.com/fckeditor/userfiles/file/64702308368.pdfIn PDF document text
    • http://mastervin.ru/files/file/wapevededupexamed.pdfIn PDF document text
    • https://datatech-int.com/userfiles/file/77039445842.pdfIn PDF document text
    • http://kingsbrite.com/kingsbrite.com/userfiles/file/59598942024.pdfIn PDF document text
    • http://effekt-film.de/files/file/96865747167.pdfIn PDF document text
    • http://szyoujin.com/UploadFile/file/20210909010445673.pdfIn PDF document text
    • https://linlinline.biz/js/ckfinder/userfiles/files/35399253347.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1615a1b9e0401f---jiwasitifojira.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/regefutatifu.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150ecfdc4bd4---jujezadodukixejapulixikub.pdfIn PDF document text
    • http://paradoxine.com/upload/files/pabulugi.pdfIn PDF document text
    • https://ip-kamera-rendszer.nuttydog.hu/ckfinder/userfiles/files/diwulax.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/1614c791f4336e---23046819559.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f7914dcfc2---12311568411.pdfIn PDF document text
    • http://giaydantuongphongkhach.net/images/news/file/58866590022.pdfIn PDF document text
    • http://kronospan-mofa-hungary.hu/editor_up/63079845267.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/61796103992.pdfIn PDF document text
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/6607f406a1df9730ae127f0d17917b95/90289765754.pdfIn PDF document text
    • https://war-old.its.vn/new/userfiles/file/zonad.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614f0124d215a---34436280424.pdfIn PDF document text
    • http://sireny.net/share/files/92516549537.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_off0000b24d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB24D 10676 bytes
SHA-256: c29f4000155706aed094b81a87a911c356d643592b8cee513a7d47d245dc7761
font_01_sfnt_off0000caab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAAB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e2bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2BD 14368 bytes
SHA-256: 6741fe00b8941fe5784950887ae0c481ec822792ceeb5bf32b81966e76bad922