Malicious PDF — malware analysis report

Static analysis result for SHA-256 31f95b895ab60e0e…

MALICIOUS

PDF

85.6 KB Created: 2021-07-23 07:18:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 93667a83791f9a14b03664b0b6c6bc6e SHA-1: d8053dd235c2859ce42ae78636bbbf4d44bad7d4 SHA-256: 31f95b895ab60e0ee124a915b5ef89b25441cf5ab4ea59e4424b33f275032d40
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document contains a large number of links, many of which point to compromised WordPress upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary attack pattern observed is the use of a link farm to direct users to potentially malicious content, likely for phishing or malware delivery.

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://vhktn.at/images/content/files/77174044856.pdf
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/4b710330031d30cf8e73c47efca90885/fazojixunixonotekaxolana.pdf
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f29decca2d---lopugakobin.pdf
    • https://bladmedyczny24.pl/wp-content/plugins/super-forms/uploads/php/files/70b8452bb048ebb0677b0e5d6e96ef21/31817725402.pdf
    • https://bouveau-consulting.com/userfiles/file/39569041786.pdf
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/4759374ec05c829b509e9dec65a885a8/rikilewusulosinater.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/cf10f90925856bfbc625509984e5c79b/gexisigafododoxig.pdf
    • https://clifestyle.net/uploades/userfiles/file/28084012290.pdf
    • http://bsp-oblspl.org/ckfinder/userfiles/files/bosoj.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/a9fb53d86cf905c815269ea65d8ed1f8/susowinuresigisu.pdf
    • https://lacaune.hu/userfiles/file/74066131428.pdf
    • http://myjobcareer.net/userfiles/file/2021052507252573499.pdf
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7a995ff4a---tufinipimawisilis.pdf
    • http://clubchic.lv/c/i/files/94005623793.pdf
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/snoe0nm91ce2t5a596u4bv25d0/48029097617.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/4a01o2cbn82g1hifnprp35koq3/66721572435.pdf
    • https://a5productions.com/home/a5pro/public_html/ckfinder/userfiles/files/21505505412.pdf
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/953e8488f34188337f89d0b30daf7dac/41201036733.pdf
    • http://wittzumstegfamilyreunion.com/clients/e/e5/e56c03c63d8c9260b12fda9e5e6a3df6/File/kufuwobudasubak.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=label+continents+and+oceans+worksheet+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_off0000eae1.bin
352590b9a947bed88b16684767b8ef1dd4d1583cd0434f60fe367b3b2e23471c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE1 16796 bytes
font_01_sfnt_off0001164e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1164E 16792 bytes
font_02_sfnt_off00012e65.bin
1deec6c42b70f7b46359e22b74576423f8740f77a3add3b963913974454e77d9
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E65 10992 bytes