Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8618d0d6adde168…

MALICIOUS

PDF

75.3 KB Created: 2021-09-21 00:47:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c41edcb9b2deeab7084db6e5f2e1ec30 SHA-1: d35e2903461b844157d63d00d38f9405bea69576 SHA-256: a8618d0d6adde1684aa57b192675baddb8a6b3cf0ff5710032a60d79cdee6f80
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS uploads, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://textstricker.de/benutzerdateien/79107533164.pdf In PDF document text
    • https://kratky.eu/files/file/pisowasemada.pdfIn PDF document text
    • https://kolbandibileklik.com/resimler/files/21086901363.pdfIn PDF document text
    • http://ppfi-online.com/userfiles/file/lemofewezivoz.pdfIn PDF document text
    • https://holcom-wd.com/webroot/img/files/zizupotop.pdfIn PDF document text
    • http://cutskytools.com/d/files/rotedate.pdfIn PDF document text
    • https://citronixdeflection.com/nbloom/fckuploads/file/foxelurajuxisare.pdfIn PDF document text
    • http://talentfuturesservices.com/sharpinstitute/images/files/29547761609.pdfIn PDF document text
    • https://kp-bs.ru/upload/files/lofejisavedije.pdfIn PDF document text
    • https://uzunlarpeynir.com/dursun/upload/files/83741269790.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/f78506ac891adfe1c82c39a98d67c8e1/seposupema.pdfIn PDF document text
    • http://misr-consult.com/userfiles/file/26342572719.pdfIn PDF document text
    • https://koncnc.com/genelresimler/file/xunuxufimikafe.pdfIn PDF document text
    • http://serting.eu/userfiles/files/34742609823.pdfIn PDF document text
    • http://megalabsrl.it/userfiles/files/sujotonofin.pdfIn PDF document text
    • http://studiolegalebisantis.it/userfiles/files/pepipuwom.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614647db43d66---86796904187.pdfIn PDF document text
    • http://millecolori.it/images/file/7270092226.pdfIn PDF document text
    • http://signexpowholesale.com/project-new/christianbook/upload_images/file/werofamiwudixujuzevuriko.pdfIn PDF document text
    • https://allora-tour.by/var/upload/file/53743092796.pdfIn PDF document text
    • http://konferencii.org/web/uploads/assets/file/gaped.pdfIn PDF document text
    • https://servicepapik.ro/files/bidewuw.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/phrj7eakhqi8eecm05op089jnk/30551909230.pdfIn PDF document text
    • http://faurau.com/luodan/images/userfiles/file/kejaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=angry+birds+game+download+for+windows+7PDF 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_off0000c3cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dbde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBDE 16612 bytes
SHA-256: ea0f9c84a3751f06f572292948d6814c68a00192de85fe46fc836bb965a0d6f1
font_02_sfnt_off0001061f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1061F 10968 bytes
SHA-256: c69a999a398ae4ab59adb6f88aa031193fadf32371ff4ad7d9de4adf8736c038