Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea1a16685d631695…

MALICIOUS

PDF

69.8 KB Created: 2021-10-01 03:36:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8ffa83b78f8f2a476a2fbe6be6cfe198 SHA-1: b58e27a207a85011d073ae130ac57ad1e02f3c1f SHA-256: ea1a16685d631695c54902cd801cf983e6b21518bc771700eb8d96dd91a9e546
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO spam. The presence of a link farm suggests an attempt to drive traffic to malicious or deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://garglob.ru/uplcv?utm_term=identifying+chemical+reactions+worksheet+answers PDF link annotation
    • http://www.armstrongre.com/files/files/76214644916.pdfIn PDF document text
    • http://kelakewangshangduchang.a9188.com/upload_files/art_files/files/20210911_044857.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/44904436952.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161491cde18119---nukeweven.pdfIn PDF document text
    • https://rusepress.com/uploads/wysiwyg/files/beriwodelanuroxufeda.pdfIn PDF document text
    • http://archpiudue.com/userfiles/files/80811412095.pdfIn PDF document text
    • https://cafemocion.com/userfiles/file/1999452224.pdfIn PDF document text
    • http://www.web-globus.de/ckfinder/userfiles/files/7825919431.pdfIn PDF document text
    • https://linhquan-group.com/upload/ck/files/52918750817.pdfIn PDF document text
    • https://gazeta-msp.pl/user_files/File/21668059019.pdfIn PDF document text
    • http://recuva.kr/upload/fck_img/1631000256/file/52275577839.pdfIn PDF document text
    • http://purepoem.com/resource/docContentImg/file/2021-10-01/edd23f34f549116d0693f383b3fb87b0.pdfIn PDF document text
    • https://negaratoto.com/contents/files/30787118801.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16144d13f26ec6---tidikumafex.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/1615626e69746f---gukajibutopat.pdfIn PDF document text
    • https://zapret-rf.org/web/img/podborky/files/54646310770.pdfIn PDF document text
    • http://lustigersteirer.at/userfiles/file/xejukofirepimin.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/67131553381.pdfIn PDF document text
    • http://vssteel1999.com/ckeditor/userfiles/files/57786561094.pdfIn PDF document text
    • http://guojingmall.com/userfiles/file///fukigivuxuvudejepe.pdfIn PDF document text
    • http://ylpqzl.com/ckfinder/userfiles/files/99011014707.pdfIn PDF document text
    • https://bdaudit.ro/userfiles/file/68301808145.pdfIn PDF document text
    • http://adirondackseafood.com/ckfinder/userfiles/files/padozod.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_off0000b1eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1EB 14940 bytes
SHA-256: 1db5e464a0432a5593f30b9d292a470302f8eaef4003ff00b6845ba84e80c356
font_01_sfnt_off0000d731.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD731 11164 bytes
SHA-256: db55a199acf29dc2cb1fae39c197782f1bd41c128f62a80de4149d66c4e3c7c5
font_02_sfnt_off0000f0f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1