Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c81d8fd35a38e52…

MALICIOUS

PDF

86.5 KB Created: 2021-06-30 05:51:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e5284277e34dbb064aca0646ae8920ea SHA-1: 71eb57f1b85a0675dee81c3c62d482271e3fad96 SHA-256: 9c81d8fd35a38e529933073689e0a626c6494802342815f71cb0bd1d4064295d
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised WordPress installations. The presence of numerous URLs, including those with UTM parameters, suggests an attempt to manipulate search engine results or direct users to phishing or malware distribution sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://wastran.ru/uplcv?utm_term=massage+and+facial+spa
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c52ac01e6---jesololisuwifugore.pdf
    • http://aiskreunion.com/clients/b/b4/b417c2091670ce0b0d78f4b231aea02c/File/numifup.pdf
    • http://skybuildinfraprojects.com/uploads/74164468379.pdf
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/16076ae01d914a---86754763627.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072d5604f624---28809113606.pdf
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606c863ee9556---sedoxezig.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16090816090d1a---74183281037.pdf
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/bd92d1a1b0158a9a177d033aefc8597d/depeturire.pdf
    • http://ilksolar.com/Images/Media/files/57399985275.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/23294654373.pdf
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7159978007---67568008271.pdf
    • http://verkaufs-akademie.com/userfiles/file/77397211840.pdf
    • http://autoshiftbid.com/fckeditor/userfiles/file/29972529780.pdf
    • https://codecs.roimages/file/93267931430.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a3739ac8ca---61366735951.pdf
    • https://gyn-koe70.de/obrazky/file/58599791372.pdf
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/3fa9e690d1f635b8556d44bdf3261593/39137988725.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076263b6212d---9233240142.pdf
    • http://zoltysnieg.pl/pliki_wyswig/files/pomupubebowogini.pdf
    • http://bvsaigonbinhduong.vn/uploads/files/16539003944.pdf
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/fdfc078f5255ca3a812108c49ff1a4f6/10078809358.pdf
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc1f80b491---nedupelajunigakuvi.pdf
    • http://qazaqbanki.kz/data/content/files/63343309.pdf
    • http://yaqeen-eg.com/userfiles/file/dabakalikofobili.pdf
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/hfva6ghrgs810o1h2bdaq9vucm/zemid.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • 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_off0000ee90.bin
cdc7403260bfe682be8cf104b114eed121ba9f0159dfb4acbfc1e8e8f407653f
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE90 17752 bytes
font_01_sfnt_off00011d5e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D5E 16792 bytes
font_02_sfnt_off00013575.bin
f4f15e350fd658da24206eed742abe7af7ba193f1b0840772e279338be35f33f
pdf-font-stream PDF embedded font (sfnt) at offset 0x13575 10472 bytes