Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9d54c982dd977be…

MALICIOUS

PDF

82.0 KB Created: 2021-08-17 08:21:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4dadafb1bc613c4669a7aa7fe96cc86d SHA-1: 5b43f5629fd80ab439a7de4f0c485916070d79ae SHA-256: c9d54c982dd977be5783cb9705394bd4e6dd08603d550029aa3be728a54551c4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm used for phishing or malware distribution. The presence of embedded URLs and the PDF structure strongly suggest it is designed to redirect users to malicious sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://tarnava.eu/user_images/file/54618374370.pdf
    • https://gertiesbloomers.com/kousumi/nulook/upload/fckimages/file/kugagubikiluvovubojujap.pdf
    • https://guijek.com/userfiles/file/42731951172.pdf
    • https://hiddencliff.kr/FileData/ckfinder/files/20210729_2A5A4D050E3F688E.pdf
    • http://akwarella.pl/user_uploads/file/potitekef.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609888ca1e0b1---fudodexukekexazifofub.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5e77387ab---befefifodeb.pdf
    • http://drivingschool-brno.eu/files/54518480259.pdf
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce711f87e18---wumibitimajezi.pdf
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1610cbdaf14e5c---18073358007.pdf
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/hg8k0cgng04ej460k0ifk2hph6/72093920119.pdf
    • https://citytrafik.nu/images/file/segoxapufufavedowu.pdf
    • http://mhinflatable.com/upload/file/vabusiruwosedap.pdf
    • http://intrinhgia.com/admin/webroot/upload/image/files/jifekukopoworixi.pdf
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086e40597be0---79045960595.pdf
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609300cbea014---4361261840.pdf
    • http://www.abcklima.hu//data/editorfile/38942009460.pdf
    • http://tjsijiqing.com/ckfinder/userfiles/files/2021/0814/01c8753042d59912691265f1af4513f2.pdf
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160851ad5aedb9---mobagibozamek.pdf
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160fd3bd0b155e---96982300628.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b10baa4ca65---kikevuvoxotajamob.pdf
    • https://narimasu-chintai.net/jcfiles/file/mokiremidifikubozawi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=active+and+passive+voice+interrogative+sentences+exercise+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_off0000dc33.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC33 16792 bytes
font_01_sfnt_off0000f445.bin
c03f5d49423ac6f9ae004c86477e97ecfa27fe2155f35cb1de5552f995d14f05
pdf-font-stream PDF embedded font (sfnt) at offset 0xF445 16284 bytes
font_02_sfnt_off00011e18.bin
566f13bb56e11210bc7d3e2ad0bc855c930650e99ce35b10ba1ec7009ad62acb
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E18 10900 bytes