Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a1c8de59d9a4c9b…

MALICIOUS

PDF

88.0 KB Created: 2021-06-28 06:50:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 918e753121fdd8f5e56d79cc542ef53c SHA-1: 3d4824fdb783d806f6e42b17e21abe17a1bcf8ed SHA-256: 3a1c8de59d9a4c9b280dd1856fab63c92f8a650cba87d6a592c26898e4f5ddbf
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to obscure the final destination. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple distinct hosts hosting similar PDF files suggests a coordinated campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b06b9ee6da1---75017637631.pdf In PDF document text
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/37546524458.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/81e02d6bf6ace20b06c2e4595a701a05/21323852022.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/6110e2c2b701ac5e8db8965a689163a9/45864985338.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be25412d450---59016722635.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160afbceb67e26---vepeju.pdfIn PDF document text
    • http://wonikqnc.com/upload/editor/file/1624648406.pdfIn PDF document text
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/6346ebbf6b4bb6d2cd69744b16dadb8c/97698325590.pdfIn PDF document text
    • https://careoncall.in/userfiles/files/38468922535.pdfIn PDF document text
    • http://topas.lt/userfiles/file/43638331071.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd98d18d83---fajudosepom.pdfIn PDF document text
    • https://nenanhduong.vn/Upload/files/14201552027.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16073175e20aac---35567552040.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/88707725194.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607c80c23e5e1---pebexofijijebeluluv.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606ec5b24f0b4---waluresojawelila.pdfIn PDF document text
    • https://accu-split.com/userfiles/files/nuleduxojudorabex.pdfIn PDF document text
    • http://houselandia.ru/files/lopixopu.pdfIn PDF document text
    • http://www.onlinetemsilci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160797bf8ce387---67930062880.pdfIn PDF document text
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16245826423152.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf4d8153b1d---pedojovoremazof.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/96852700115.pdfIn PDF document text
    • http://medicapoland.pl/uploaded/file/gumanubexibiw.pdfIn PDF document text
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/ccdf4fdb11b42d15587a91ac205f2286/10542016960.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=in+dehydration+synthesis+of+a+carbohydratePDF 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_off0000f430.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF430 10732 bytes
SHA-256: 60938040ae57da9a516c53af7266fcf0f7dccda6d2132c9a2f70333266553348
font_01_sfnt_off00010cc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CC9 16748 bytes
SHA-256: 7b42fe88951379a9a25946229085ce3858a8f9bff6b81759bb2ca748e05975b9
font_02_sfnt_off00013883.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13883 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1