Malicious PDF — malware analysis report

Static analysis result for SHA-256 c93e9d360a93e3fc…

MALICIOUS

PDF

76.8 KB Created: 2021-08-16 06:18:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: efc92b6826f868a33b4ba19ed0ba0d36 SHA-1: 75ec5a2453ee219a8c4855aba56b96362c96ce3f SHA-256: c93e9d360a93e3fc6e57aa189479e3df3320c6505925bef0c44ce18ca20dc58c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links. No scripts were extracted, but the structure and URL analysis are sufficient to infer the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9934

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://noithatdangcap.vn/app/webroot/uploads/files/6049910047.pdf In PDF document text
    • http://zerosquareonline.com/file/zetomexadet.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3b94286a8578edde88ed44653684083a/57466900585.pdfIn PDF document text
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/a3b36f23d9433504af47229aea599e49/wokoxebaruwubaminaroj.pdfIn PDF document text
    • https://easypayindia.in/userfiles/file/zozinakopilebusudu.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/1610a710a45a5a---82496436324.pdfIn PDF document text
    • http://tnshoppingbag.com/upfiles/file/wupoxumosi.pdfIn PDF document text
    • http://purpledoorchurch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075930aeb428---puwonanaribuzuxosad.pdfIn PDF document text
    • http://asiadomainstore.com/userfiles/file/97863143466.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a8a844284e0---83675177827.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/160b5f6db9dcf1---89068033341.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/252rrkjbfakm8ov3t49vnt1140/fazufevazilujozapenidabi.pdfIn PDF document text
    • https://kozmetikadunakeszi.hu/userfiles/file/75950728498.pdfIn PDF document text
    • https://elpmarketing.ca/wp-content/plugins/super-forms/uploads/php/files/ef11238aee3d87abd59bb31cae6b6454/midovarokalupexixo.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608bf9a0cc564---85998444167.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a463ce8f566---13035006648.pdfIn PDF document text
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/4e0jor1vi79i8h224p8invf2g4/66009779500.pdfIn PDF document text
    • http://unicaconsultoriarh.com/images/files/lipedomojovineto.pdfIn PDF document text
    • http://creaorganization.com/depo/sayfaresim/file/90615599767.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/161175899eaf90---64218207087.pdfIn PDF document text
    • https://camphacement.vn/upload/files/viroziwepikagev.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/c15c7d1ea653366281fbff176109ae4e/77060627298.pdfIn PDF document text
    • http://homeopathyhk.com/files/piwemozofoxirinipuga.pdfIn PDF document text
    • http://nsdadventist.org/FCKData/file/pijazuzevozofodiwu.pdfIn PDF document text
    • http://explosivedevices.ru/media/file/38528020270.pdfIn PDF document text
    • http://allnatureint.com/userfiles/file/telezuriwoxo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=suzuki+violin+book+1+piano+accompaniment+perpetual+motionPDF 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_off0000c85c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC85C 10952 bytes
SHA-256: c0784c0cdd41d9f3b9c19713d59e54cfd0223b1b44550d90137b7c2d6ac10b91
font_01_sfnt_off0000e1a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f9b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9B3 16284 bytes
SHA-256: 3da06d0971dd601c8dd99326abfd8a0fb356d8352d56a8b58c63f5e5ffd4c6a5