Malicious PDF — malware analysis report

Static analysis result for SHA-256 829311c18acf2637…

MALICIOUS

PDF

69.8 KB Created: 2021-09-27 10:37:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 025cd1a447a2b57c198c5fef83b593b9 SHA-1: c4e5f6f1aa52733b5e9ab104c10e1b021f59e84e SHA-256: 829311c18acf2637883d0823616db412370c2222c0ede17a3aebd8ad93570d42
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to lure users to malicious content. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classification strongly supports its malicious nature. The presence of external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://irlanc.ru/uplcv?utm_term=how+to+get+miracast+on+my+phone PDF link annotation
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/6fc31d8188c14e07e3350248946d50b7/fuxuwasekobefuxoz.pdfIn PDF document text
    • http://puntolinea.org/userfiles/files/24357002749.pdfIn PDF document text
    • http://studioarclab.eu/userfiles/files/gedazipefomanakat.pdfIn PDF document text
    • https://pima-alarms.eu/slicice/file/84081142988.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/1024374626.pdfIn PDF document text
    • http://veterinariacasettamattei.it/userfiles/files/woxarofiludikorixob.pdfIn PDF document text
    • http://4bx.pl/public/file/97286416988.pdfIn PDF document text
    • http://www.ks-klinika.ru/ckfinder/userfiles/files/26997824021.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e02072d59a---9795979620.pdfIn PDF document text
    • http://samtekelektrik.com/files/71062262770.pdfIn PDF document text
    • https://sandipkumardutta.com/ckfinder/userfiles/files/70888285267.pdfIn PDF document text
    • http://samtle.net/ckupload/files/simovigarunafobupasegi.pdfIn PDF document text
    • http://hasanmasat.com/ckfinder/userfiles/files/gegegewamuruperetewiki.pdfIn PDF document text
    • http://aalzkj.love-mrt.com/upload/files/noruja.pdfIn PDF document text
    • https://123natura.com/stockages/files/56668569459.pdfIn PDF document text
    • http://rickgrisolia.com/userfiles/files/77232790596.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/fuvoxibikenipukerizus.pdfIn PDF document text
    • https://sudahhabis.com/contents/files/kunikiwazopixepate.pdfIn PDF document text
    • http://machinesupplier.cn/data/product/file/2021923_04758_529.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149024256111---67926627746.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e18041210b---48925909023.pdfIn PDF document text
    • https://koratspring.com/upload/file/pesazukulelewi.pdfIn PDF document text
    • http://abnigakgdsg.friendship-match.com/upload/files/liwugugesazejunufelu.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_off0000b153.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB153 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c96a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC96A 10968 bytes
SHA-256: 02c048e03ebc30f0b1b3902cd1e3186994e5d2b5bdb684f343bc9308aa6fd42e
font_02_sfnt_off0000e2ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2BA 15232 bytes
SHA-256: de7f80302b4e0231faa8d5b2d04c240a253b550d47c8c6254effcb3cdbd83ad2