Malicious PDF — malware analysis report

Static analysis result for SHA-256 316a8af043f76439…

MALICIOUS

PDF

69.9 KB Created: 2021-10-03 19:50:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 8d22ed47fe23f3728eab856c64fb1ecb SHA-1: 9cbbc3b531af2fbd06055265f99eae90840c555b SHA-256: 316a8af043f76439acc6b37343e975f40ba9aca8cbd95deae1a2232cfcf2dedc
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 compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://queure.ru/uplcv?utm_term=concord+watch+serial+number+lookup PDF link annotation
    • http://darstin.com/userfiles/files/novikev.pdfIn PDF document text
    • https://megalight.lv/uploads/files/83905045138.pdfIn PDF document text
    • http://jedzenie365.pl/ckfinder/userfiles/files/67811826739.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16134d822989b8---loxilulifod.pdfIn PDF document text
    • http://hanart21.com/files/userfiles/file/97260408917.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16159412278d28---dukutij.pdfIn PDF document text
    • http://maasmartcity.com/userfiles/file/babovozafigililowego.pdfIn PDF document text
    • http://megalaserasia.com/upload///87631347806.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0d8562a7b---nesowiromagaxedusipum.pdfIn PDF document text
    • https://www.q-jin.ne.jp/ckfinder/userfiles/files/pusojapajexizotonike.pdfIn PDF document text
    • https://cylinder96.ru/admin/ckfinder/userfiles/files/67944402600.pdfIn PDF document text
    • https://petek.biz/resimler/files/kodosulu.pdfIn PDF document text
    • http://platcometals.com/images/file/soguzapuzafopi.pdfIn PDF document text
    • http://kmjmt.com/news/upload/file/211003143539902448f0kmz5.pdfIn PDF document text
    • https://ozmutludokum.com/userfiles/file/gavomunelefuvura.pdfIn PDF document text
    • http://bxbrdh.marketsearching.com/upload/files/30689995524.pdfIn PDF document text
    • http://technocom.pl/editor/file/96746331363.pdfIn PDF document text
    • https://academiapreprod.riportico.com/userfiles/files/mujumejud.pdfIn PDF document text
    • http://hzzxtl.com/UploadFile/file/20210928183653345.pdfIn PDF document text
    • https://avigailpekelman.com/sites/default/files/file/74935405933.pdfIn PDF document text
    • https://envirotechindia.net/admin/userfiles/file/walovapewosa.pdfIn PDF document text
    • http://dekoblickfang.de/userfiles/file/88161749381.pdfIn PDF document text
    • http://vilniausgreziniai.lt/userfiles/file/54841173424.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_off0000af70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF70 11228 bytes
SHA-256: f7d594871cb878c18d721ef2bb613f97d6012a4667c3f4b56beb6b67cfc4c15f
font_01_sfnt_off0000c967.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC967 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e179.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE179 16020 bytes
SHA-256: 5b619d6a6c408a943fcd1eae8448c7b3580d69a3ad1ac6cc31464fe60100583e