Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8c8a4ac0dcd63da…

MALICIOUS

PDF

87.3 KB Created: 2021-09-04 00:49:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 31f89643a505021ea94d097be188f86d SHA-1: 113159711626f3e452fbc097a328bf57c2fc281f SHA-256: f8c8a4ac0dcd63da1ce85e0b9b7991a903ab9fbf471e8bb2a616c4888f4c9802
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm hosted on multiple compromised websites, suggesting a phishing or malware distribution attempt. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely instructs the user to open a password-protected archive, a common tactic to bypass security scanners. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9921

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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=manual+for+bosch+ascenta+dishwasher
    • http://cgpharma.in/cote_dor_import/admin/ckfinder/userfiles/files/74079566304.pdf
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e203708dcc---27676050138.pdf
    • http://kppzp.pl/userfiles/file/rumen.pdf
    • https://landbar.com/upload/files/12407108400.pdf
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612696f824bff---38249619584.pdf
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/2688e49b3d670b2f97aba2dc1b6bd4ea/94217685713.pdf
    • http://banhangcongnghe.com/upload/FCK/file/13796578386.pdf
    • http://aceonlinementors.com/userfiles/file/9928970927.pdf
    • https://lee-trading.tw/archive/upload/files/25510503316.pdf
    • http://pune-india.info/userfiles/file/fanerovaluxo.pdf
    • https://baxsporthorses.nl/userfiles/file/89686250885.pdf
    • http://ceskylakros.cz/userfiles/file/9556729116.pdf
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/ja1sj0d5tp4bg3clufmujubrr1/24674227103.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/3fkr5f6sbdbngirhl3d5quaph5/xirimaxenalatata.pdf
    • http://uzks.hr/upload/datoteke/81657712964.pdf
    • http://www.brickchamber.com/ckfinder/userfiles/files/wosuminekogoxopujulu.pdf
    • http://mintaialuminum.com/d/files/10381212222.pdf
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160d69f16766b4---26586469294.pdf
    • https://seeyounow.net/userfiles/file/delibetagukij.pdf
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/sdpc5sg64k1lav5dpl2ij7ssac/fuvoza.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076b49361284---3534221137.pdf
    • http://aspbae.org/userfiles/file/9236686193.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160d6ae287f173---79193641486.pdf
    • http://bclgrouptt.com/userfiles/file/duxinix.pdf
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/f335vegcasehagqjb22phf7nk1/mixavezekegoxepudi.pdf
    • http://aquarium-kochi.com/app/webroot/ckfinder/userfiles/files/71146851003.pdf
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f6bd.bin
d895e53340bf7084fb74778bd465127b73130da7c14bc679e2681387a3e8520f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BD 10892 bytes
font_01_sfnt_off00010fee.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FEE 16792 bytes
font_02_sfnt_off00012800.bin
98cde767b572b12388d3638033cd66a1a5190f883cbda8050e0ecb757c0c36dd
pdf-font-stream PDF embedded font (sfnt) at offset 0x12800 17880 bytes